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DROUGHT ANALYSIS USING CORDEX SIMULATIONS OVER THE
MEDITERRANEAN CLIMATE REGIONS OF TURKEY
A THESIS SUBMITTED TO
THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES
OF
MIDDLE EAST TECHNICAL UNIVERSITY
BY
ANIL YILDIRIM POYRAZ
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR
THE DEGREE OF MASTER OF SCIENCE
IN
CIVIL ENGINEERING
APRIL 2018
iii
Approval of the thesis:
DROUGHT ANALYSIS USING CORDEX SIMULATIONS OVER THE
MEDITERRANEAN CLIMATE REGIONS OF TURKEY
submitted by ANIL YILDIRIM POYRAZ in partial fulfillment of the requirements
for the degree of Master of Sciences in Civil Engineering Department, Middle
East Technical University by,
Prof. Dr. Halil Kalıpçılar
Dean, Graduate School of Natural and Applied Sciences
Prof. Dr. İsmail Özgür Yaman
Head of Department, Civil Engineering
Prof. Dr. İsmail Yücel
Supervisor, Civil Engineering Dept., METU
Examining Committee Members:
Prof. Dr. Elçin Kentel
Civil Engineering Dept., METU
Prof. Dr. İsmail Yücel
Civil Engineering Dept., METU
Assoc. Prof. Dr. M. Tuğrul Yılmaz
Civil Engineering Dept., METU
Assoc. Prof. Dr. Önder Koçyiğit
Civil Engineering Dept., Gazi University
Assoc. Prof. Dr. Ceylan Talu Yozgatlıgil
Statistics Dept., METU
Date: 27/04/2018
iv
I hereby declare that all information in this document has been obtained and
presented in accordance with academic rules and ethical conduct. I also declare
that, as required by these rules and conduct, I have fully cited and referenced
all material and results that are not original to this work.
Name, Last Name : Anıl Yıldırım POYRAZ
Signature :
v
ABSTRACT
DROUGHT ANALYSIS USING CORDEX SIMULATIONS OVER THE
MEDITERRANEAN CLIMATE REGIONS OF TURKEY
Poyraz, Anıl Yıldırım
M.Sc., Department of Civil Engineering
Supervisor : Prof. Dr. İsmail Yücel
April 2018, 154 pages
Drought has been a significant result of climate change that causes variance on
precipitation regimes. Mediterranean region is one of the hotspots of the world in this
respect. Dry summers and rainy winters -the characteristic of this climate type- makes
this region more vulnerable to the effects of climate change. Hence, it is important to
monitor drought considering the increasing population and economic facilities in the
regions that are under Mediterranean climate conditions in Turkey. This study aims
to assess the trends in drought by applying the Standardized Precipitation Index(SPI)
for 5 timescales – from 1 month to 12 months. The model grid data that corresponds
to meteorological stations distributed from south to west within the study area was
obtained from 12 different Global Circulation Model / Regional Climate Model
couplings of CORDEX project. Observed and modeled prediction data were
compared for reference period (1971-2005) in order to detect the most reliable
models. Afterwards, modified Mann-Kendall trend test was applied on the SPI and
annual precipitation values for the entire period (1972-2100). The trends were
vi
estimated by linear regression for the locations in which Mann-Kendall results
indicated a significant change. In conclusion, a persistent increasing drought trend
was detected for Muğla and western Antalya parts such that all models are coherent.
On the other hand, the divergence of the trends for some regions according to
different models signifies the discrepancy of models. Besides, the drought trends are
decreasing for some regions (especially Southern Marmara) as the timescale
increases.
Keywords: Climate change, drought, Standardized Precipitation Index,
Mediterranean climate region, CORDEX project
vii
ÖZ
CORDEX SİMÜLASYON VERİLERİ KULLANILARAK TÜRKİYE’NİN
AKDENİZ İKLİM BÖLGELERİNDE KURAKLIK ANALİZİ
Poyraz, Anıl Yıldırım
Yüksek Lisans, İnşaat Mühendisliği Bölümü
Tez Yöneticisi : Prof. Dr. İsmail Yücel
Nisan 2018, 154 sayfa
Yağış rejimlerinde değişimlere sebep olan iklim değişikliğinin önemli sonuçlarından
biri de kuraklıktır. Akdeniz Bölgesi bu açıdan Dünyadaki hassas noktalardan biridir.
Bu iklim tipinde yazların kurak, kışların yağışlı olması bölgeyi iklim değikliğinin
etkilerine daha açık hâle getirmiştir. Bu sebeple, Türkiye’nin Akdeniz iklimi etkisi
altındaki bölgelerinde artan nüfus ve ekonomik etkinlikler de düşünüldüğünde
kuraklığı incelemek oldukça önemlidir. Bu çalışmada, Standartlaştırılmış Yağış
İndeksi(SPI) 1 aydan 12 aya kadar 5 zaman ölçeğinde uygulanarak kuraklıktaki
trendler değerlendirilmiştir. 12 farklı iklim modelinin, incelenen alanının güneyinden
batısına yayılmış meteorolojik gözlem istasyonlarının konumuna denk gelen yağış
verileri CORDEX projesinden alınmıştır. En güvenilir modelleri belirlemek amacıyla
referans dönemi (1971-2005) için gözlem ve model yağış verileri karşılaştırılmıştır.
Ardından, düzenlenmiş bir Mann-Kendall testi tüm dönem için (1972-2100) SPI ve
yıllık yağış değerlerine uygulanmıştır. Mann-Kendall testinin anlamlı değişim işaret
ettiği noktalar için lineer regresyon yöntemiyle trendler hesaplanmıştır. Sonuçta,
viii
Muğla ve Batı Antalya için kuraklıkta tüm modellerin sonuçlarının uyum içinde
olduğu ciddi bir artış trendi tespit edilmiştir. Öte yandan, bazı bölgeler için model
sonuçların çeşitliliği, modellerin farklılıklarına işaret etmektedir. Ayrıca, Güney
Marmara başta olmak üzere bazı bölgelerde zaman ölçeği arttıkça kuraklık trendinde
azalış sözkonusudur.
Anahtar kelimeler: İklim değişikliği, kuraklık, Standartlaştırılmış yağış indeksi,
Akdeniz iklim bölgesi, CORDEX projesi
ix
ACKNOWLEDGEMENTS
I would like to express my deepest gratitude to my supervisor Prof.Dr. İsmail Yücel
for his patient guidance and precious advices throughout the research.
I would like to thank my dear labmate Rizwan Aziz for his valuable help which made
this thesis possible.
I thank my friends Ezgi Kıyıcı, Özgün Emre Koç, Çiğdem Aygün and Yasinalp Örsel
for their support throughout thesis study. Lastly, I would like to thank my cat Kumpir
who never left me alone along the study nights.
x
TABLE OF CONTENTS
ABSTRACT ........................................................................................................... v
ÖZ ....................................................................................................................... vii
ACKNOWLEDGEMENTS ...................................................................................ix
TABLE OF CONTENTS ........................................................................................ x
LIST OF FIGURES ............................................................................................. xii
LIST OF TABLES ............................................................................................... xiv
ABBREVIATIONS ............................................................................................. xvi
CHAPTERS
1. INTRODUCTION .............................................................................................. 1
Introduction .................................................................................................. 1
The Significance of the Study ....................................................................... 5
Literature Review ......................................................................................... 6
Description of Thesis .................................................................................. 10
2. DATA, STUDY AREA AND METHODS ........................................................ 11
Data and Study Area ................................................................................... 11
Study Area ........................................................................................... 11
Observation Data .................................................................................. 13
Model Data ........................................................................................... 13
2.2. Methods...................................................................................................... 16
Standardized Precipitation Index .......................................................... 18
Modified Mann-Kendall Test ................................................................ 22
xi
Linear Regression ................................................................................ 23
Statistics Used for Measuring Model Performance ............................... 24
3. RESULTS ........................................................................................................ 25
Performance of the Models ........................................................................ 25
Daily Evaluations................................................................................. 25
Monthly Evaluations ............................................................................ 36
3.2. Effects of Time Duration in SPI Analysis ................................................... 43
3.3. Modeled trend analysis of SPI-3, -12, and annual precipitation at selected
stations ............................................................................................................. 46
3.4. The Slope of Trend Analysis of SPI and Annual Precipitation From Ensemble
Model Results ................................................................................................... 52
SPI 1 .................................................................................................... 53
SPI 3 .................................................................................................... 63
SPI 6 .................................................................................................... 72
SPI 9 .................................................................................................... 79
SPI 12 .................................................................................................. 85
Annual Precipitation ............................................................................ 92
Changes in the Frequency of Drought Between the Mid and End of the Century
............................................................................................................ 101
Areal Extension of Drought within the period .......................................... 115
4. SUMMARY, CONCLUSION AND RECOMMENDATIONS ....................... 119
REFERENCES .................................................................................................. 122
APPENDICES
A. MATLAB CODES .................................................................................. 126
B. TREND SLOPE TABLES ....................................................................... 131
xii
LIST OF FIGURES
FIGURES
Figure 1. The distribution of annual precipitation for Turkey based on the period
1981-2010 (Downloaded from WEB4).................................................................... 2
Figure 2 Classification of drought depending on duration and effects (Downloaded
from WEB7). .......................................................................................................... 4
Figure 3. Illustration of Hadley Circulation (Heffernan, 2016). Dry zones are
extending as Hadley cell is shifting polewards. ....................................................... 7
Figure 4. Mediterranean climate regions on the Earth (Downloaded from WEB8). 12
Figure 5. Climate map of Turkey (Downloaded from WEB9). .............................. 12
Figure 6. Inner square surrounds EURO-CORDEX domain area (Stagge et al., 2015)
............................................................................................................................. 13
Figure 7. The locations of model data for projection period ................................... 16
Figure 8. The steps of the study based on the data and operations used. ................. 17
Figure 9 Example of an equiprobability transformation from a fitted gamma
distribution to the standard normal distribution (Hughes and Saunders, 2002) ....... 20
Figure 10 Obtaining linear regression line ............................................................. 23
Figure 11. Daily mean precipitation of entire area for reference period.................. 27
Figure 12. Seasonally grouped boxplot of monthly precipitation for entire area ..... 37
Figure 13. Plot of monthly precipitation means of observation and models. The bars
on model mean line show the standard deviation gap of 12 models. ...................... 38
Figure 14. Monthly precipitation means of observation and models ...................... 39
Figure 15. SPI values for Muğla station according to model 1-1 predictions (1972-
2100). The linear regression equation is on top-right hand corner. ......................... 44
Figure 16. Annual precipitation for all models with stacked lines .......................... 49
Figure 17 The study area with province names ...................................................... 52
Figure 18 The geographical distribution of trends for SPI 1. The legend is valid for
rest of the SPI trend maps ..................................................................................... 56
xiii
Figure 19. The geographical distribution of trends for SPI 3 ..................................65
Figure 20. The geographical distribution of trends for SPI 6 ..................................73
Figure 21. The geographical distribution of trends for SPI 9 ..................................79
Figure 22. The geographical distribution of trends for SPI 12 ................................86
Figure 23. The geographical distribution of trends for annual rainfall ....................94
Figure 24. Changes in the frequency of drought. ‘Mod’, ‘sev’ and ‘ext’ indicate
moderately, severely and extremely dry classes respectively. .............................. 103
Figure 25. The percentage of the stations under dry conditions ............................ 115
Figure 26. The average percentage of the stations under dry conditions for all models
............................................................................................................................ 117
xiv
LIST OF TABLES
TABLES
Table 1. Location of the observation stations (* signifies the locations which were
only studied in projection)..................................................................................... 14
Table 2. Model data list. ‘Model no’ numbering was given to provide a convenience
throughout the thesis. ............................................................................................ 15
Table 3 SPI value interpretation (Mckee et al., 1993) ............................................ 21
Table 4. Correlation coefficient(CORR) and Root mean square error(RMSE) values
for moving averages of daily means ...................................................................... 31
Table 5. Correlation coefficient(CORR) and Root mean square error(RMSE) values
for successive monthly .......................................................................................... 32
Table 6. Correlation coefficient(CORR) and root mean square errors(RMSE) analysis
for seasonally grouped months .............................................................................. 34
Table 7. Trends in annual precipitation for reference period (1971-2005). ↘ denotes
negative slope, ↔ denotes no significant trend, ↗ denotes positive slope. ............. 35
Table 8. The statistics of coupled models for projection period ............................. 36
Table 9. The statistics for coupled models for projection period ............................ 36
Table 10. Trend change table for 5 stations. ↘ denotes negative slope, ↔ denotes no
significant trend, ↗ denotes positive slope. ........................................................... 48
Table 11. Trend slope values for model 1-1 ......................................................... 131
Table 12. Trend slope values for model 1-2 ......................................................... 133
Table 13. Trend slope values for model 1-3 ........................................................ 135
Table 14. Trend slope values for model 1-4 ........................................................ 137
Table 15. Trend slope values for model 2-1 ........................................................ 139
Table 16. Trend slope values for model 2-2 ........................................................ 141
Table 17. Trend slope values for model 2-3 ........................................................ 143
Table 18. Trend slope values for model 3-1 ........................................................ 145
xv
Table 19. Trend slope values for model 3-2 ....................................................... 147
Table 20. Trend slope values for model 3-3 ....................................................... 149
Table 21. Trend slope values for model 4-1 ....................................................... 151
Table 22. Trend slope values for model 4-2 ....................................................... 153
xvi
ABBREVIATIONS
CLMcom Climate Limited-area Modelling Community
CNRM Météo-France/Centre National de Recherches Météorologiques
CORDEX Coordinated Regional Climate Downscaling Experiment
CORR Correlation Coefficient
DMI Danish Meteorological Institute
GCM General Circulation Model/Global Climate Model
IPCC Intergovernmental Panel on Climate Change
IPSL Institut Pierre-Simon Laplace
KNMI Royal Netherlands Meteorological Institute
MGM Turkish State Meteorological Service
MOHC Met Office Hadley Centre
NASA The National Aeronautics and Space Administration
RCM Regional Climate Model
RCP Representative Concentration Pathways
RMSE Root Mean Square Error
SMHI Swedish Meteorological and Hydrological Institute
SPI Standardized Precipitation Index
1
CHAPTER 1
INTRODUCTION
Introduction
Water moves in a cycle on the earth and in the atmosphere. It evaporates from the
surface of the earth, cools and condenses as it rises into atmosphere, and falls again
to the surface in different forms of precipitation (WEB1).
Climate is the typical and averaged weather of a region or a city over many years.
Climate characteristics consist of many attributions from seasonal temperature
differences to precipitation regimes. Changes in climate take several years - decades,
centuries and even millennials (WEB2).
Frequent and precise measurements of any form of precipitation is indispensable to
determine changes in and make models of Earth’s water cycle. In addition to
observations, climate models reproduce observed features of recent climate and past
climate changes by benefiting well-established physical principles to (Randall et al.,
2007). A General Circulation Model (also known as Global Climate Model and
abbreviated as GCM) can provide reliable prediction information on big scales
(around 1000 by 1000km) while Regional Climate Models applied over a limited area
and driven by GCMs can provide information on much smaller scales (WEB3). This
improves assessing the changes in precipitation regimes in many vulnerable regions
of the world.
2
Turkey is a country that has a climatic diversity though it is situated in large
Mediterranean location. This diversity of climatic conditions is mainly due to diverse
nature of the landscape. The mountains in the south and north coast run parallel to
the seashore and therefore marine climate cannot penetrate to the interior parts. Only
the western parts are relatively more open to marine effects since the mountains are
not parallel to the shore, but perpendicular.
The climatic differences between regions of Turkey can be figured out by
geographical distribution of annual precipitation (
Figure 1) Annual rainfall along Mediterranean Sea and Aegean Sea varies from 580
to 1,300 millimeters, depending on location whilst Black Sea coast receives the
highest annual rainfall (Sensoy et al., 2016). The amount of rainfall decreases
gradually to the inland. Only a small part from the east of the country receives
precipitation as much as coastline.
Figure 1. The distribution of annual precipitation for Turkey based on the period
1981-2010 (Downloaded from WEB4)
3
The increasing concentration of greenhouse gases leads the atmosphere to be warmer
as a result of trapped solar energy. This phenomenon is called ‘global warming’
which refers to global temperature rises for long-term, whereas ‘climate change’ is a
broader term that indicates not only the changes in averages but also increases in
occurrence of extreme events like floods, drought and heatwaves or changes in rain
and snow patterns (WEB2).
Drought is a bit latent phenomenon comparing to other extreme weather events since
it is not as instantaneous as floods that emerge in minutes or heatwaves that evokes
itself immediately. However, it is such an event that has widespread and long-termed
effects to nature and society. Even, mass migration of people is one of the striking
results of these effects (Raleigh et al., 2008). The cost of drought must also be taken
into account at evaluation of its damage. The estimation of the cost of a four-year
drought that hit California is 2.7 billion US Dollars in 2015, according to a study
from University of California-Davis (WEB5). At the beginning of 2018, an increase
in electricity price was discussed due to decreases in electricity production of
hydropower plants in consequence of drought in Turkey (WEB6).
Since precipitation is a vital component of water cycle, the changes in climate directly
affect the spatial and temporal distribution and quantity of precipitation. Assessing
the changes and trends in precipitation and concluding about drought is an arguable
issue as well as essential. This complexity arises from the problem of defining
drought. Redmond(2002) explains drought simply ‘insufficient water to meet needs’
following a discussion on the approaches to the phenomenon. This definition
highlights the importance of both the supply and the demand sides of the subject
(Redmond, 2002).
Wilhite and Glantz (1985) endeavored to categorize the drought. They categorized
the definitions into four: meteorological, hydrological, agricultural,
and socioeconomic.
4
Meteorological definitions are the most common and define drought usually based
on the degree of dryness and the duration of the dry period. Definitions of
meteorological drought must be considered separately for every region since the
meteorological conditions that result in deficiencies of precipitation are highly
irregular from region to region.
Agricultural drought associates numerous characteristics (precipitation shortages,
soil water deficits etc.) of meteorological drought to agricultural impacts. A useful
definition of agricultural drought should consider the variable susceptibility of crops
at different stages of crop growth.
Figure 2 Classification of drought depending on duration and effects (Downloaded
from WEB7).
5
Hydrological drought is linked with the effects of duration of precipitation shortfalls
on surface or subsurface water supply (WEB7). This type of droughts is mostly out
of phase with both meteorological and hydrological droughts since it takes longer to
show up precipitation deficiencies on hydrological system components such as soil
moisture, streamflow, and groundwater and reservoir levels.
A variety of indices have been proposed and used to assess drought up to now.
However, developing an index to assess drought is an inseparable matter from
defining drought. Thus, quantifying drought by indices is a difficult geophysical
endeavor. Standardized Precipitation Index(SPI) is a meteorological drought index
that is widely used to detect drought for different timescales. Keyantash and Dracup
(2002) finds out that SPI is the most successful index in measuring drought right after
rainfall deciles. They analyze 14 types of indices from all drought forms
(meteorological, hydrological and agricultural) based on six criteria: robustness,
tractability, transparency, sophistication, extendability, and dimensionality. SPI is
also distinguished with its ability to measure the severity of drought and selected to
measure drought in this study owing to all these features of it.
The Significance of the Study
The main goal of this study is to investigate the drought conditions from past to the
end of 21st century in Mediterranean climate region of Turkey that is most vulnerable
to the effects of climate change because of the increase in temperature and decrease
in precipitation (Dabanlı et al., 2017; Topcu et al., 2010). The drought analyses were
performed by calculating the well-known SPI values for drought at 1, 3, 6, and 12
months timescales, assessing the impact of drought at different levels, i.e.
meteorological, hydrological and agricultural droughts. Ensemble modeling
approach releases 12 GCM/RCM pairs from CORDEX (the Coordinated Regional
Climate Downscaling Experiment) project was used to make drought predictions not
only for the past but also future period till the end of century. First, in reaching the
6
main goal of this study, the performance analyses of the GCM/RCMs pairs in
estimating monthly precipitation that are used to derive SPI indices were made at 46
grid locations corresponding to meteorological stations distributed to the study area.
Second, the Mann Kendall trend test was applied to SPI values calculated through the
period from 1972 to 2100 for each model pair. Finally, the assessment of drought at
various magnitudes was performed at locations where drought is statistically
significant from multi-model system over entire study area. As a result, the
consistency of drought that appears within the region by the end of century was
documented with the support of ensemble model approach.
Literature Review
IPCC reports (2013) revealed that decreases in soil moisture and increases in
agricultural drought are likely in presently dry regions by the end of 21st century
according to the projections from regional to global scale under RCP8.5 scenario.
The drying in soil moisture is also consistent with projected changes in Hadley
circulation (Figure 3) and surface temperature increases in Mediterranean,
Southwestern US and Southern African regions (IPCC, 2013). In addition to this,
Giorgi (2006) highlighted the vulnerability of Mediterranean and North Eastern
European regions by defining them the climate change hot-spots.
An extensive research that was conducted by Cook et al. (2016) investigated the
drought for the whole region around Mediterranean Sea. They analyzed the drought
variability for 900 years (1100-2012) in the Old World Drought Atlas (OWDA), a
spatiotemporal tree ring reconstruction of the June-July-August self-calibrating
Palmer Drought Severity Index. The outcomes indicated an east-west coherence in
drought on multidecadal and centennial timescales. However, the analysis results of
Levant region (Cyprus, Israel, Jordan, Lebanon, Palestine, Syria, and Turkey)
indicated that recent dry extremes are extraordinary during the last millennium. This
7
provided a support to studies claiming that the anthropogenic climate change has a
significant effect (Cook et al., 2016).
Figure 3. Illustration of Hadley Circulation (Heffernan, 2016). Dry zones are
extending as Hadley cell is shifting polewards.
Many studies have been done based on the evaluation of the performance of the
climate models and making predictions depending upon them. The followings
provide a summary of the results of some of these studies.
Giorgi and Lionello (2008) determined that GCM and RCM simulations are generally
similar to each other at large scale. Though, it was pointed that precipitation change
signal produced by RCMs also take into the orographically effects account.
8
Leng et al. (2015) investigated climate change impacts on drought in China. They
detected the different response of same models (HadGEM2-ES and MIROC-ESM-
CHEM) for different drought types. Predicting more extreme droughts than mean
droughts is another significant result of their study.
Osuch et al. (2016) analyzed SPI and rainfall trends for Poland with RCM projections
from ENSEMBLES project. These analyses were conducted for a period that consists
both historical and future data: 1971-2099. Bias correction was applied to model data,
though, the trends in SPI slightly changed after correction. Considering the
consistency of the models, it was detected that the results are similar for some models
for the study area. Modified Mann-Kendall test was used for trend detection in this
study. Lee et al. (2017) determined the influence of climate change and possible rises
on drought conditions for Hwanghae Plain in Korea with regionally downscaled data.
Stagge et al. (2015) investigated future meteorological drought based on CORDEX
data for RCP 4.5 and RCP 8.5 scenarios. They highlighted the conflicting results of
previous studies on drought severity even though their consistency on regional
hotspots and CORDEX project’s capacity to improve the reliability and consistency
of the analyses since the projections have been processed at a much finer resolution.
The results of this study indicated significant increases in meteorological drought
frequency and severity for Mediterranean region while areal extensions were likely
for Atlantic coast and Southern Europe according to period 1971-2000. It was also
detected that the changes in the occurrence of moderate and severe droughts and the
affected area were regardless of the long-term emission scenarios for the near term
(2011-2040). Additionally, the increase scenarios in drought are consistent around
Mediterranean for both scenarios.
Kara et al. (2016) investigated climate change impacts on extreme precipitation of
Ömerli catchment in İstanbul by using ensemble climate modeling. The ensembles
of daily precipitation time series from 15 different RCMs driven by 5 different GCMs
under A1B climate change projections obtained through EU-ENSEMBLES project
for two periods: reference (1960-1990) and future (2071-2100). An increase in
9
extreme precipitation in winter, spring and summer is expected while a decrease in
autumn is likely according to the results. They also used the geographically weighted
regression (GWR) method to downscale climate change impacts to this small
catchment and GWR provided significant modifications to these changes and agreed
on the direction of change from RCMs.
There are many studies dedicated to analyze the drought for entire Turkey and certain
basins of Turkey’s Mediterranean climate region as well. Sönmez et al. (2005) found
out that drought vulnerability of Turkey for varying time steps portrayed diverse but
consistent picture. Their study also revealed varying trends for different regions in
terms of drought severity and duration. While the southeastern and eastern parts of
Turkey are more open to moderate droughts at short timescales, the impact would be
anticipated less at the coastal part since the droughts are only effective at longer
durations and occur at moderate levels. Nevertheless, coastal and interior parts more
tend to occur severe droughts. These facts bring negative consequences for different
sectors that needs water for varying periods of the year. Interior parts will suffer from
agricultural drought whilst hydrological drought will occur at longer time steps at the
coastal parts.
Türkeş (2012) revealed briefly the effects of climate change in a study that examines
the observed and projected drought and desertification in Turkey. The effects of
global warming were considered with evaluating the changes in extremes in this
study. It is important that the results based on a modified standardized precipitation
index(MSPI) showed increase in drought severity for the regions under
Mediterranean climatic conditions and the inland parts of the country which is
neighbor to this climate region. The vulnerability of Turkey with respect to intensive
and broad winter droughts -which are related to high positive modes of North Atlantic
Oscillation- is critical as well.
Unlike the other studies that are dedicated to determine the effects of climate change,
Türkeș et al. (2016) also inquired if the climate of Turkey is really changing in a study
10
that compared two consecutive time periods: 1950-1980 and 1981-2010. They
detected some variations in the present geographical patterns of climate regions.
Increasing precipitation amounts in the northern and eastern regions in contrast to
decreasing amounts in the west, central and southern regions were serious outcomes
of this study.
Gümüş and Algın (2017) examined the relation between meteorological and
hydrological drought for Seyhan-Ceyhan River Basins using SPI and SDI
(Streamflow Drought Index). They found that a meteorological drought demonstrates
hydrological drought for the following year. This result is crucial for water
management with more frequent and severe droughts.
Description of Thesis
In the first chapter of the thesis, a brief information about climate change, GCM-
RCM simulations and drought indices are given. The previous studies are also
mentioned in this chapter. Details about data, study area and methods are explained
in the following chapter. The third chapter presents the results of analysis. The results
are discussed in chapter 4. The last chapter provides the summary, conclusions and
recommendations.
11
CHAPTER 2
DATA, STUDY AREA AND METHODS
Data and Study Area
Study Area
Mediterranean climate is a major climate type of the Köppen classification and
characterized by hot, dry summers and cool, wet winters. The regions which under
this climatic condition are located between about 30° and 45° latitude north and south
of the Equator and on the western sides of the continents (Kottek et al., 2016). Figure
4 shows five Mediterranean climate regions on the Earth.
This region presents several aspects of interest, such as its important inter-annual
variability in precipitation and temperature, and the severe economic
damages and losses of life due to droughts, flooding events or heat or cold waves
occurred in the last decades, together with an increase in population and infrastructure
(Easterling et al., 2000). In this study, the climatic conditions were mainly taken into
consideration at determination of study area rather than other identifiers like regional
or provincial borders. Climate frontiers are not very certain and differ a bit from one
map to other for Turkey. Still, the maps are consistent in general. Climate regions
showed in
Figure 5 were taken as a basis at determination of study area in the thesis. Only a
small part consisting of the north and east coast of the Marmara Sea was not studied.
12
Figure 4. Mediterranean climate regions on the Earth (Downloaded from WEB8).
Figure 5. Climate map of Turkey (Downloaded from WEB9).
13
Observation Data
Observed precipitation data for monthly rainfall was obtained from MGM (Turkish
State Meteorological Service) for 46 stations to evaluate the performance of model
data (Table 1). This evaluation period was also called ‘reference period’, which refers
to the period 1971-2005. The stations were selected homogeneously for the whole
study area as much as possible (Figure 7).
Model Data
Model data was selected from Eur11 domain (Figure 6), that includes data in
0.11degree (~12.5 km) resolution. This is the highest resolution produced in
CORDEX project (WEB10).
Figure 6. EURO-CORDEX domain area surrounded by the inner square (Stagge et
al., 2015)
14
Table 1. Location of the observation stations (* signifies the locations which were
only studied in projection)
Station Name Latitude Longitude Station Name Latitude Longitude
BANDIRMA 40.35 27.97 KARAİSALI 37.27 35.07
AYVALIK 39.32 26.70 MANAVGAT 36.78 31.43
DİKİLİ 39.07 26.88 ERDEMLİ 36.62 34.30
AKHİSAR 38.92 27.85 CEYHAN 37.03 35.82
KUŞADASI 37.87 27.25 DÖRTYOL 36.85 36.22
DİDİM* 37.48 27.27 ISLAHİYE 37.03 36.63
BODRUM 37.05 27.43 GAZİPAŞA 36.27 32.32
DALAMAN 36.75 28.78 YUMURTALIK 36.77 35.78
ANAMUR 36.08 32.83 SAMANDAĞ 36.08 35.97
SİLİFKE 36.38 33.93 ACIPAYAM 37.42 29.33
İSKENDERUN 36.58 36.17 TEFENNİ 37.32 29.77
FİNİKE 36.30 30.15 GEMLİK* 40.44 29.15
KAŞ* 36.20 29.65 KARACABEY* 40.13 28.33
SALİHLİ 38.48 28.13 MUDANYA* 40.37 28.90
SEFERİHİSAR 38.35 26.83 M.KEMALPAŞA* 40.04 28.40
ÖDEMİŞ 38.23 27.97 AYVACIK* 39.61 26.40
NAZİLLİ 37.92 28.32 OSMANIYE* 37.08 36.25
ELMALI 36.75 29.92 ALANYA* 36.55 32.025
MUT 36.65 33.43 MANISA 38.62 27.43
KARATAŞ 36.57 35.38 IZMIR 38.43 27.17
*MENEMEN 38.58 27.07 AYDIN 37.85 27.85
FETHİYE 36.62 29.12 DENIZLI 37.78 29.08
MARMARİS 36.85 28.27 MUGLA 37.22 28.37
BURHANİYE* 39.50 26.98 ANTALYA 36.88 30.7
MİLAS 37.32 27.78 MERSIN 36.8 34.6
YATAĞAN 37.35 28.13 ADANA 37 35.33
KOZAN 37.45 35.82 ANTAKYA 36.2 36.17
DATÇA 36.75 27.67 BALIKESİR* 39.63 27.88
KÖYCEĞİZ* 36.97 28.68 CANAKKALE 40.15 26.42
KORKUTELİ 36.75 30.20 BURSA 40.18 29.07
15
Model data was obtained for 12 models from CORDEX project (Table 2). RCM-
GCM couplings was made of 4 different Global Climate Models (in other words
Driving Models) and 6 Regional Climate Models. The producers of the RCMs were
stated for information purposes.
Table 2. Model data list. ‘Model no’ numbering was given to provide a convenience
throughout the thesis.
Model No GCM Institute RCM
1-1
ICHEC-EC-EARTH
DMI HIRHAM5
1-2 CLMcom CCLM4-8-17
1-3 KNMI RACMO22E
1-4 SMHI RCA4
2-1
CNRM-CERFACS-CNRM-CM5
CNRM ALADIN53
2-2 CLMcom CCLM4-8-17
2-3 SMHI RCA4
3-1
MOHC-HadGEM2-ES
CLMcom CCLM4-8-17
3-2 KNMI RACMO22E
3-3 SMHI RCA4
4-1 IPSL-IPSL-CM5A-MR
SMHI RCA4
4-2 IPSL-INERIS WRF331F
The model data was extracted for 60 locations (Figure 7) from CORDEX data grids.
46 of these were used in performance analysis since reliable data could be obtained
for 46 observation stations. On the other hand, all of 60 locations were analyzed for
future projection. RCP 8.5 - the scenario of highest greenhouse gas emission- was
considered for future in the study.
16
Figure 7. The locations of model data for projection period
2.2. Methods
In this part, the process of analysis was introduced. Estimation methods that were
applied to precipitation data and SPI values are stated as well. Figure 8 describes the
analysis steps.
17
Figure 8. The steps of the study based on the data and operations used.
18
Standardized Precipitation Index
The Standardized Precipitation Index is a meteorological drought index that was
introduced by Mckee et al. (1993). It interprets observed precipitation as a
standardized departure with respect to a rainfall probability distribution function
(Keyantash and Dracup, 2002). The calculation of SPI value for desired period is
based on the long-term precipitation record. Guttman (1999) recommends at least 50
years of data for a reliable calculation.
The calculation of SPI begins with modeling the monthly precipitation time series
using different statistical distributions (Lloyd-Hughes and Saunders, 2002). The first
is the gamma distribution, whose probability distribution is defined as
g(x) =1
βαΓ(α)xα−1e−x/β for x > 0 (1)
where, α > 0 is shape parameter, β > 0 is scale parameter, and x > 0 is the amount of
monthly precipitation. Γ(α) is the gamma function, which is defined as
Γ(α) = limn→∞
∏n! ny−1
y + υ≡ ∫ ya−1
∞
0
n−1
υ=0
e−ydy
(2)
Fitting the distribution to the monthly precipitation data requires estimating α and β.
Edwards and McKee (1997) suggest using the approximation of Thom (1958) to
estimate these parameters as follows:
α =1
4A(1 + √1 +
4A
3)
(3)
β =
x
α
(4)
19
where, for n observations
Α = ln(x) −
∑ ln (x)
n
(5)
The expression of cumulative probability G(x) of an amount of precipitation
occurring for a given month and timescale is yielded by integrating the probability
density function with respect to x and inserting the estimates of α and β:
G(x) = ∫ g(x)dx =
1
βαΓ(α)
x
0
∫ xαx
0
e−x β⁄ dx
(6)
Substituting t for x/^β reduces Equation (6) to
G(x) =1
Γ(α)∫ tα−1e−1dt
x
0
(7)
which is the incomplete gamma distribution function. Since the gamma distribution
is undefined for x = 0, and q = P(x = 0) > 0 where P(x = 0) is the probability of zero
precipitation, the cumulative distribution becomes
H(x) = q + (1 − q)G(x) (8)
The cumulative probability distribution is then transformed into the standard normal
distribution to obtain the SPI value. This process is illustrated in Figure 9. The first
panel shows the empirical cumulative probability distribution for a 3-month average
December–January–February (DJF) of precipitation over the south east of England
for the period 1901–99. Over-plotted is the theoretical cumulative probability
distribution of the fitted gamma distribution. The second panel indicates the standard
normal cumulative probability. To convert a given precipitation level to its
corresponding SPI value, first locate the precipitation value on the abscissa of the
left-hand panel, draw a perpendicular, and locate the point of intersection with the
20
theoretical distribution. Then project this point horizontally (maintaining equal
cumulative probability) until it intersects with the graph of standard normal
cumulative probability. The intersection between a line drawn vertically downward
from this point and the abscissa determines the SPI value (1.1 in this example for 77
mm precipitation).
The above approach is not practical for calculating the SPI for large numbers of data
points. The approximate conversion provided by Abramowitz and Stegun (1965) can
be employed as an alternative following Edwards and McKee (1997):
Z = SPI = − (t −
c0 + c1t + c2t2
1 + d1t + d2t2 + d3t3) for 0 < H(x) ≤ 0.5
(9)
Z = SPI = + (t −
c0 + c1t + c2t2
1 + d1t + d2t2 + d3t3) for 0.5 < H(x) ≤ 1
(10)
Figure 9 Example of an equiprobability transformation from a fitted gamma
distribution to the standard normal distribution (Hughes and Saunders, 2002)
21
In this thesis, the index values were obtained via a MATLAB code that is stated in
Appendix A.
McKee and others used a classification system based on SPI values to define drought
intensities as shown in Table 3 . It extends from extremely wet to extremely dry.
Table 3 SPI value interpretation (Mckee et al., 1993)
The SPI can be computed for any chosen timescales from 1 month to 48 months. This
flexibility is a powerful feature of the SPI that provides useful information unless we
have a clear idea of the desired intervals. In this study SPI was calculated for five
intervals (1,3,6,9 and 12 months) for given periods. Afterwards, trends of SPI values
were evaluated for these five intervals consecutively.
It should be noticed that SPI values were shown and analyzed since 1972 instead of
1971. This difference arose from the nature of SPI calculation. To obtain the SPI 12
value the former 12 months precipitation data is required. Namely, the first SPI 12
value was calculated for the first month of 1972. Then, the SPI values at shorter
timescales were also assessed from 1972 to provide consistency with SPI 12.
22
Modified Mann-Kendall Test
Mann Kendall test (Mann, 1945 ; Kendall, 1975) is one of the widely used non-
parametric tests for detecting trends in time series. The Mann-Kendall trend test is
derived from a rank correlation test for two groups of observations proposed by
Kendall (1975). The correlation between the rank order of the observed values and
their order in time is the key part of Mann-Kendall trend test. However, a modified
Mann– Kendall test has been developed in order to avoid problems with
autocorrelation (Hamed and Ramachandra Rao, 1998). The Mann-Kendall test
statistics S calculated from the following equation:
S = ∑ ∑ sgn(xj − xk) =
n
j=k+1
n−1
k=1
{
+1 if (xj − xk) > 0
0 if (xj − xk) = 0
−1 if (xj − xk) < 0
(11)
Where, number of data is n. Additionally, the correction ratio n/nS* is introduced
during the calculation of a variance of the S statistics to account for an effect of serial
correlation.
var∗(S) = var(S)n
nS∗
(12)
n
nS∗ = 1 +
2
n(n − 1)(n − 2)∑(n − i)(n − i − 1)(n − i
n−1
i=1
− 2)ρS(i)
(13)
where, ρS denotes the autocorrelation function.
Since we are detecting the trend in SPI values, it is important to use such a modified
trend test that considers serial correlation. This test was also applied to annual
precipitation in order to detect any relation with drought. The significance level was
23
taken 0.05 (95% confidence level) for the all trend tests performed in this study. The
MATLAB code that was used in calculation is stated at Appendix A.
Linear Regression
The slopes of the trendlines were obtained by linear regression. This linear approach
models the relationship between a response variable y (SPI and rainfall) and one or
more explanatory variables (years) denoted x. Since negative values of SPI denotes
dry conditions, negative slope means increasing drought.
Figure 10 illustrates how a regression line is fitted to variables. The predicted values
of y are denoted by ŷ whose equation includes two constants: intercept (w0) and slope
(w1).
y = w0 + w1x (14)
Figure 10 Obtaining linear regression line
24
Statistics Used for Measuring Model Performance
Root mean square error (RMSE) values of the model precipitation data were
estimated for reference period to analyze the reliability of the models. It is one of the
methods that are used to measure the closeness of model data to real values along
with correlation coefficient (CORR). Schaller et al. (2011) evaluate climate models
by ranking their RMSE and CORR values. They use an updated version of the model
ranking performed by Reichler and Kim (2008).
RMSE is calculated by following equation which is based on the difference between
observed and model data values:
RMSE = √∑ (Pi − Oi)
2ni=1
n
(15)
where, O denotes amount of observed precipitation while P denotes predicted
precipitation and n denotes number of data.
The correlation coefficient of two random variables is a measure of their linear
dependence. If each variable has n scalar observations, then the Pearson correlation
coefficient (r) is defined as
r =
∑ (xi − x)(yi − yni=1
√∑ (xi − x)2ni=1 √∑ (yi − y)2n
i=1
(16)
where, xi and yi are the single samples (observation and model values) indexed
with i; x and y are the sample means.
25
CHAPTER 3
RESULTS
Performance of the Models
In the first step of analysis, the observed and model precipitation data were compared
for the reference period 1971-2005. The averages of daily and monthly precipitation
were compared at the same time as long term statistics were calculated and evaluated.
Daily Evaluations
The plots in Figure 11 demonstrate the mean precipitation of each day of year for
reference period. In addition, 31-days moving averages were plotted for both
observation and model data.
Daily averages of model 1-1 well correlated with observation means (Figure 11a).
However, summer and autumn daily means slightly underestimated observation as
well as partially underestimated observed daily mean precipitation for winter and
spring seasons. Model 1-2 diverged from observation averages for almost the entire
year (Figure 11b). This model overestimated observation for spring and summer days
while underestimated in autumn and winter. Model 1-3 correlated with observation
for autumn (Figure 11c). Still, the daily averages of spring overestimated observation.
Summer and winter are the two seasons which daily averages of model 1-3 partially
overestimated and underestimated observation. Summer, autumn and winter daily
means of model 1-4 diverged from observation as well as model correlated with
observation means overall (Figure 11d).
26
Model 2-1 and 2-2 greatly diverged from observed means (Figure 11e and Figure
11f). Both models overestimated summer precipitation. Overestimation carried on for
model 2-2 autumn daily means while model 2-1 underestimated observation winter
daily averages. Model 2-3 well correlated with observation though it is forced by
same GCM with model 2-1 and 2-2 (Figure 11g). Besides, the mean values are very
close to observation at model 2-3.
Model 3-1 correlated with observation to some extent (Figure 11h). Despite, it
overestimated observation means for winter, spring and autumn seasons. Model 3-2
greatly overestimated observation for winter, spring and summer seasons (Figure
11i). Model 3-3 (Figure 11j) well correlated with observation like models 1-4 and 2-
3 which are forced by same RCM: RCA4. Though, model 3-3 underestimated
observation daily means for autumn and winter seasons.
Model 4-1 underestimated observation daily averages for entire year (Figure 11k).
The divergence is greater for winter and spring seasons. Model 4-2 did not correlate
with observation as well as the model daily means greatly overestimated observation
for spring and summer seasons (Figure 11l).
27
Figure 11. Daily mean precipitation of entire area for reference period.
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
a) Model: 1-1
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
b) Model: 1-2
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
c) Model: 1-3
28
Figure 11. (cont’d)
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
d) Model: 1-4
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
e) Model: 2-1
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
f) Model: 2-2
29
Figure 11. (cont’d)
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
g) Model: 2-3
0
1
2
3
4
5
6
7
8
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
h) Model: 3-1
0
1
2
3
4
5
6
7
8
9
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
i) Model: 3-2
30
Figure 11. (cont’d)
0
1
2
3
4
5
6
7
1
14
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Da
ily m
ea
n p
recip
. (m
m)
Days of year
j) Model: 3-3
0
1
2
3
4
5
6
7
114
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
k) Model: 4-1
0
1
2
3
4
5
6
7
1
14
27
40
53
66
79
92
105
118
131
144
157
170
183
196
209
222
235
248
261
274
287
300
313
326
339
352
365
Daily m
ean p
recip
. (m
m)
Days of year
l) Model:4-2
31
Table 4 shows CORR and RMSE values for moving averages based on daily means
of the models. Predictions of three models (1-1, 2-3, 1-4) are well correlated with
observed values according to statistics. Daily mean values of model 1-3 predictions
are not far from observed means while correlation is relatively low for this model.
For model 4-1, analysis of daily means revealed opposite situation: The values
differed greatly for all days of the year while followed similar seasonal variation with
observed values (Figure 11k and Table 4).
Table 4. Correlation coefficient(CORR) and Root mean square error(RMSE) values
for moving averages of daily means
Rank Model No CORR Model No RMSE
1 1-1 0.9923 2-3 0.27
2 2-3 0.9908 1-1 0.31
3 1-4 0.9795 1-3 0.45
4 4-1 0.9734 1-4 0.46
5 3-2 0.9565 3-3 0.49
6 3-1 0.9458 1-2 0.56
7 1-3 0.9349 3-1 0.63
8 3-3 0.9264 4-1 0.76
9 1-2 0.8908 2-2 0.79
10 2-2 0.8895 4-2 0.82
11 4-2 0.8663 3-2 0.87
12 2-1 0.5198 2-1 1.08
Table 5 and Table 6 show the CORR and RMSE values for monthly data. 420
monthly precipitation values (from 1971 to 2005) were ordered and analyzed
successively to obtain the outcomes in Table 5. These monthly values were grouped
seasonally and analyzed to obtain Table 6 as well. Since correlation coefficients are
32
relatively low for a reliable evaluation, RMSE values have been discussed rather than
CORR values.
Table 5. Correlation coefficient(CORR) and Root mean square error(RMSE) values
for successive monthly
Rank Model No CORR Model No RMSE
1 3-2 0.3976 4-1 72.58
2 2-3 0.3900 1-4 73.62
3 1-1 0.3881 2-3 74.87
4 3-3 0.3857 1-2 76.62
5 1-4 0.3828 1-3 77.10
6 4-1 0.3768 3-3 78.89
7 3-1 0.3647 1-1 79.02
8 1-3 0.3242 3-1 83.87
9 1-2 0.2946 2-1 84.90
10 2-2 0.2434 2-2 85.00
11 4-2 0.2148 3-2 88.10
12 2-1 0.1434 4-2 90.23
Seeing the RMSE ranking in Table 5, the difference of RMSE values between rank
7 and 8 can be considered as a threshold. The values increased almost with a 1.00
mm/month interval till 7th ranked model while a 4.00 mm/month increase occurred at
8th rank. Models 1-1, 1-4, 2-3, 3-3 and 4-1 are distinguished from these 7 top models
in RMSE ranking along with their high ranks in CORR ranking.
Outcomes of daily means statistics indicated both consistency and divergency for
different models. Models 1-4, 2-3 and 3-3 showed consistency with observation
values according to daily means as well as they are in top ranks in RMSE analysis
33
(Figure 11d, Figure 11g, Figure 11j and Table 4) . However, it should be noticed that
a few models from top ranks in Table 4 diverged from observation daily means
especially for spring season. RMSE values for spring months also indicated this
divergency: models 1-1, 1-2 and 1-3 ranks at 7th, 11th and 8th place for spring
respectively (Table 6). However, the seasons can be ordered as autumn, spring,
summer and winter in terms of the CORR values of models. The models projected
the best performance during autumn and the worst in winter.
34
Table 6. Correlation coefficient(CORR) and root mean square errors(RMSE)
analysis for seasonally grouped months
Rank
Winter Spring
Model
No CORR
Mo
del
No
RMSE Model
No CORR
Mod
el
No
RMSE
1 2-3 0.1056 2-1 102.61 2-3 0.1974 4-1 60.36
2 3-1 0.1046 2-2 102.61 1-1 0.1568 2-3 62.01
3 3-2 0.0806 4-1 102.76 3-3 0.1401 3-3 62.93
4 2-2 0.0795 1-2 103.02 4-1 0.1320 1-4 63.54
5 2-1 0.0699 1-4 104.75 1-4 0.1202 3-2 64.52
6 1-4 0.0585 2-3 105.04 3-1 0.1126 3-1 65.88
7 1-1 0.0546 3-1 109.41 3-2 0.1033 1-1 65.99
8 3-3 0.0448 1-3 109.83 1-3 0.0945 1-3 69.25
9 4-1 0.0431 4-2 113.29 2-2 0.0932 2-1 69.50
10 1-2 0.0091 3-3 113.73 1-2 0.0536 2-2 72.28
11 1-3 -0.0242 1-1 115.61 2-1 0.0388 1-2 72.32
12 4-2 -0.0375 3-2 124.26 4-2 0.0282 4-2 77.04
Rank
Summer Autumn
Model
No CORR
Mo
del
No
RMSE Model
No CORR
Mod
el
No
RMSE
1 2-1 0.1613 1-3 25.09 3-2 0.3136 4-1 69.81
2 3-1 0.1324 1-1 25.13 3-3 0.3055 1-4 70.99
3 1-3 0.1230 1-4 26.16 2-3 0.3021 1-3 74.17
4 3-2 0.1082 4-1 29.31 1-1 0.2859 2-3 74.19
5 1-2 0.1080 3-3 29.40 1-4 0.2642 1-1 74.67
6 4-1 0.0906 1-2 32.04 4-1 0.2629 1-2 74.93
7 2-2 0.0867 3-2 32.16 1-3 0.2516 3-3 78.61
8 1-1 0.0867 2-3 33.11 3-1 0.2294 2-1 79.07
9 4-2 0.0850 3-1 39.38 4-2 0.1904 2-2 88.04
10 2-3 0.0828 2-2 66.33 1-2 0.1896 4-2 88.70
11 1-4 0.0519 4-2 66.85 2-2 0.1895 3-1 96.44
12 3-3 0.0296 2-1 68.96 2-1 0.1448 3-2 97.78
35
Table 7 indicates the trends in annual rainfall for five locations for reference period.
These locations were selected since they are well representing the study area. Models
1-1, 2-2 and 4-2 predicted significant trend for few stations though no significant
trend was detected according to observation and rest of the models. This result can
be considered as a negative outcome on reliability of these three models. Though,
Table 7 indicates that the models are generally trustable in trend analysis.
Table 7. Trends in annual precipitation for reference period (1971-2005). ↘ denotes
negative slope, ↔ denotes no significant trend, ↗ denotes positive slope.
Obs 1-1 1-2 1-3 1-4 2-1 2-2 2-3 3-1 3-2 3-3 4-1 4-2
Adana ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↗
Antalya ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔
Balıkesir ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔
İzmir ↔ ↘ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔
Muğla ↔ ↘ ↔ ↔ ↔ ↔ ↘ ↔ ↔ ↔ ↔ ↔ ↔
Table 8 and Table 9 show the mean and standard deviation values of daily
precipitation simulated by different GCM/RCM pairs for period 1971-2100. These
two tables enable comparing the initiative effects of GCMs and RCMs.
The mean standard deviation of various RCMs with the same GCM model is 1.804
(Table 8) while the mean deviation value of different GCMs with the same RCM is
1.644 (Table 9). This implies the greater impact from RCM models than that from
GCM models on daily precipitation. The uncertainty that comes from RCM models
is higher than that from GCM models in daily precipitation simulation during period
1971-2100.
36
Table 8. The statistics of coupled models for projection period
Model
No GCM RCM mean
mean of
means
standard
deviation
mean
of s.d.
s.d. of
s.d.
1-2 ICHEC-EC-
EARTH
CCLM4-8-17 1.697
1.708
1.491
1.804
0.129572 1-3 RACMO22E 1.913 1.727
1-4 RCA4 1.515 1.516
3-1 MOHC-
HadGEM2-ES
CCLM4-8-17 2.193
2.160
1.932
0.263024 3-2 RACMO22E 2.526 2.329
3-3 RCA4 1.761 1.832
Table 9. The statistics for coupled models for projection period
Model
No GCM RCM mean
mean of
means
standard
deviation
mean
of s.d.
s.d. of
s.d.
1-2 ICHEC-EC-EARTH
CCLM4-
8-17
1.697
2.079
1.491
1.644
0.240143 2-2 CNRM-CERFACS-
CNRM-CM5 2.348 1.546
3-1 MOHC-HadGEM2-ES 2.193 1.932
1-4 ICHEC-EC-EARTH
RCA4
1.515
1.691
1.516
0.174796 2-3
CNRM-CERFACS-
CNRM-CM5 1.796 1.544
3-3 MOHC-HadGEM2-ES 1.761 1.832
Monthly Evaluations
Figure 12 shows boxplots of monthly precipitation from all models and observation
for each season. Each box includes values from 46 locations for reference period. In
addition to this, the mean of the models for monthly precipitation values including
whole stations were shown in Figure 13. The bars around model means denote the
standard deviations of 12 model pairs.
37
Fig
ure
12.
Sea
sonall
y g
rouped
bo
xp
lot
of
mo
nth
ly p
recip
itat
ion f
or
enti
re a
rea
38
The ensemble mean of monthly precipitation values is very near to observation for
most of the months (Figure 13). However, monthly rainfall predictions of a few
models caused a significant divergence of model means from observation means for
the months January, February, May, June and December.
Figure 13. Plot of monthly precipitation means of observation and models. The bars
on model mean line show the standard deviation gap of 12 models.
It can be distinguished which models caused such a divergence at model means by
Figure 14. Models 2-1, 2-2 and 4-2 overestimated summer rainfalls while 2-1
underestimated winter rainfalls. 3-2 overestimated autumn and winter rainfalls as
well. Models 2-1, 2-2, and 4-2 yielded highly meaningless monthly precipitation from
winter months to summer months when they were compared with observed
precipitation.
39
Figure 14. Monthly precipitation means of observation (Obs) and models (Model)
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
a) Model 1-1
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
b) Model 1-2
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
c) Model 1-3
40
Figure 14. (cont’d)
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
d) Model 1-4
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
e) Model 2-1
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
f) Model 2-2
41
Figure 14. (cont’d)
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
g) Model 2-3
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
h) Model 3-1
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
i) Model 3-2
42
Figure 14. (cont’d)
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
j) Model 3-3
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
k) Model 4-1
0
20
40
60
80
100
120
140
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ly P
recip
itation (m
m)
l) Model 4-2
43
3.2. Effects of Time Duration in SPI Analysis
The plots in Figure 15 show the successive SPI values for 5 timescales and trendlines
obtained by linear regression for model 1-1 predictions between the years 1972-2100
on Muğla location. This location was considered at this step since modified Mann-
Kendall test results pointed a significant change in trends for all timescales. The
negative slope in SPI signifies increase in drought as negative SPI values mean dry
conditions. Thus, these plots indicate increasing drought condition for Muğla.
Further, the magnitude of trendline slope increases in negative direction as timescale
increases. This can be interpreted as the drought increase is not limited at
meteorological scale.
The significance of dry and wet periods within the evaluation period is more evident
with increasing time duration from 1-month to 12 months in SPI values (Figure 15).
Fluctuations in SPI with wet and dry values are reduced and they become more
compact. For example, with the longer duration the drought condition changes its
phase (level) from meteorological to agricultural drought and finally it may reach to
the level of hydrological drought. If the drought with its magnitude and duration is
persistent, it may be referred as agricultural to hydrological drought (SPI 9 and 12).
44
Figure 15. SPI values for Muğla station according to model 1-1 predictions (1972-
2100). The linear regression equation is on top-right hand corner.
y = -0.0004x + 0.3395
-5
-4
-3
-2
-1
0
1
2
3
4
5197
2197
6198
0198
4198
8199
2199
7200
1200
5200
9201
3201
7202
2202
6203
0203
4203
8204
2204
7205
1205
5205
9206
3206
7207
2207
6208
0208
4208
8209
2209
7
a) SPI 1 for Muğla
SPI1 Linear Regression Line
y = -0.0006x + 0.4416
-5
-4
-3
-2
-1
0
1
2
3
4
5
197
2197
6198
0198
4198
8199
2199
7200
1200
5200
9201
3201
7202
2202
6203
0203
4203
8204
2204
7205
1205
5205
9206
3206
7207
2207
6208
0208
4208
8209
2209
7
b) SPI 3 for Muğla
SPI3 Linear Regression Line
45
Figure 15. (cont’d)
y = -0.0007x + 0.5322
-5
-4
-3
-2
-1
0
1
2
3
4
5
197
2197
6198
0198
4198
8199
2199
7200
1200
5200
9201
3201
7202
2202
6203
0203
4203
8204
2204
7205
1205
5205
9206
3206
7207
2207
6208
0208
4208
8209
2209
7
c) SPI 6 for Muğla
SPI6 Linear Regression Line
y = -0.0008x + 0.6518
-5
-4
-3
-2
-1
0
1
2
3
4
5
197
2197
6198
0198
4198
8199
2199
7200
1200
5200
9201
3201
7202
2202
6203
0203
4203
8204
2204
7205
1205
5205
9206
3206
7207
2207
6208
0208
4208
8209
2209
7
d) SPI 9 for Muğla
SPI9 Linear Regression Line
46
Figure 15. (cont’d)
3.3. Modeled trend analysis of SPI-3, -12, and annual precipitation at selected
stations
Table 10 demonstrates the trend analysis results for 5 stations from different parts of
Mediterranean climate region of Turkey. This table indicates the consistency and
divergency of model predictions.
There is no significant trend in drought and annual rainfall according to four of the
models on Adana location. The forcing effect of Global Climate Models can be
inferred since three of these four models (2-1, 2-2, 2-3) are forced by same GCM
(CNRM-CERFACS-CNRM-CM5). Model 4-2 predicted no significant change at
trend for this location.
y = -0.0008x + 0.6219
-5
-4
-3
-2
-1
0
1
2
3
4
5197
2197
6198
0198
4198
8199
2199
7200
1200
5200
9201
3201
7202
2202
6203
0203
4203
8204
2204
7205
1205
5205
9206
3206
7207
2207
6208
0208
4208
8209
2209
7
e) SPI 12 for Muğla
SPI Linear Regression Line
47
Almost all models predicted an increase in drought and decrease in annual rainfall
for Antalya and Muğla locations while the analysis results are divergent for other
three locations. Only model 4-2 diverged from rest of the models since no significant
trend was detected for Muğla.
Balıkesir is the location in which relatively wetter conditions are expected. The
models did not predict an increasing drought for both 3-monthly and 12-monthly
scales except 3 of them (1-2, 3-1, 4-1). Further, model 3-2 predicted an increase in
SPI 12 that signifies wetter conditions.
The increase in drought at İzmir location is limited at 3 monthly scale for model 1-1,
1-3 and 2-2. However, models 1-2, 1-4, 2-3, 3-1, 3-2, 3-3 and 4-1 predicted a negative
slope at SPI trendline for not only 3-monthly but also 12-monthly scale. Lastly, a
decreasing annual rainfall accompany the increasing drought according to half of the
models. Model 4-2 predicted wetter conditions unlike the other 11 models.
Table 10 also enables detecting the forcing effect of Regional Climate Models. This
case is particularly obvious at Balıkesir and İzmir locations. Model 1-2 (forced by
CCLM4-8-17 RCM) predicted drier conditions for Balıkesir in contrast to other three
models which are forced by same GCM: ICHEC-EC-EARTH. IPSL-IPSL-CM5A-
MR GCM is also susceptible to RCM effect. The results are totally different on 4 of
5 locations for 2 models: 4-1 and 4-2.
The prediction divergence of the models on İzmir is similar to Balıkesir. Models 1-
2, 1-4, 2-3, 3-1, 3-2, 3-3 and 4-1 predicted drier conditions on İzmir location
considering SPI 3 and SPI 12 trends together. The forcing effect of RCA4 RCM is
significant since slope of all predictions forced by this RCM are at the same direction
no matter which GCM is forcing. Model 4-2 predicted wetter conditions in contrast
to other 11 models.
48
Table 10. Trend change table for 5 stations. ↘ denotes negative slope, ↔ denotes
no significant trend, ↗ denotes positive slope.
Locati
on
Analysed
trendlines
Model No
1-1 1-2 1-3 1-4 2-1 2-2 2-3 3-1 3-2 3-3 4-1 4-2
Adan
a
SPI 3 ↘ ↘ ↘ ↘ ↔ ↔ ↘ ↘ ↘ ↘ ↘ ↔
SPI 12 ↘ ↘ ↘ ↔ ↔ ↔ ↔ ↘ ↘ ↘ ↘ ↔
Annual ↘ ↘ ↘ ↘ ↔ ↔ ↔ ↘ ↘ ↘ ↘ ↔
An
taly
a
SPI 3 ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘
SPI 12 ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘
Annual ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘
Bal
ıkes
ir SPI 3 ↔ ↘ ↔ ↘ ↔ ↔ ↔ ↘ ↔ ↔ ↘ ↔
SPI 12 ↔ ↘ ↔ ↔ ↔ ↔ ↔ ↘ ↗ ↔ ↘ ↔
Annual ↔ ↘ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↔ ↘ ↔
İzm
ir
SPI 3 ↘ ↘ ↘ ↘ ↔ ↘ ↘ ↘ ↘ ↘ ↘ ↗
SPI 12 ↔ ↘ ↔ ↘ ↔ ↔ ↘ ↘ ↘ ↘ ↘ ↗
Annual ↔ ↘ ↔ ↘ ↔ ↔ ↘ ↘ ↔ ↘ ↘ ↗
Mu
ğla
SPI 3 ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↔
SPI 12 ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↔
Annual ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↘ ↔
Stacked line plots show the magnitude of fluctuations between years and the trends
along with the period (Figure 16). The upper lines in the y-axes show the higher
variability between the years and towards the origin the lines follow smoother curve.
These plots help us to identify the models, which indicate the largest and smallest
inter annual variability in precipitation and their general trend tendency along the
years. For example, these two features, general trend tendency and level of inter
annual variability among models appeared distinctly in Antalya and Muğla (Figure
16b and 16e respectively).
49
Figure 16. Annual precipitation for all models with stacked lines
197
2
197
7
198
2
198
7
199
2
199
7
200
2
200
7
201
2
201
7
202
2
202
7
203
2
203
7
204
2
204
7
205
2
205
7
206
2
206
7
207
2
207
7
208
2
208
7
209
2
209
7
Sta
cked lin
es f
or
annual ra
infa
ll
a) Adana
197
2
197
7
198
2
198
7
199
2
199
7
200
2
200
7
201
2
201
7
202
2
202
7
203
2
203
7
204
2
204
7
205
2
205
7
206
2
206
7
207
2
207
7
208
2
208
7
209
2
209
7
Sta
cked lin
es f
or
annual ra
infa
ll
b) Antalya
50
Figure 16. (cont’d)
197
2
197
7
198
2
198
7
199
2
199
7
200
2
200
7
201
2
201
7
202
2
202
7
203
2
203
7
204
2
204
7
205
2
205
7
206
2
206
7
207
2
207
7
208
2
208
7
209
2
209
7
Sta
cked lin
es f
or
annual ra
infa
ll
c) Balıkesir197
2
197
7
198
2
198
7
199
2
199
7
200
2
200
7
201
2
201
7
202
2
202
7
203
2
203
7
204
2
204
7
205
2
205
7
206
2
206
7
207
2
207
7
208
2
208
7
209
2
209
7
Sta
cked lin
es f
or
annual ra
infa
ll d) İzmir
51
Figure16. (cont’d)
197
2
197
7
198
2
198
7
199
2
199
7
200
2
200
7
201
2
201
7
202
2
202
7
203
2
203
7
204
2
204
7
205
2
205
7
206
2
206
7
207
2
207
7
208
2
208
7
209
2
209
7
Sta
cked lin
es f
or
annual ra
infa
ll e) Muğla
52
3.4. The Slope of Trend Analysis of SPI and Annual Precipitation From
Ensemble Model Results
Following the methodology and methods presented in previous chapter, future
changes in drought and rainfall were analyzed. The corresponding data of 12
CORDEX models was extracted for 60 locations -which have the same locations with
the observation stations of the counties in the study area. SPI indices were analyzed
for 1,3,6,9 and 12 monthly timescales based on the predicted monthly precipitation
values between 1972-2100. Afterwards the trends of SPI indices and annual rainfall
for each location were tested in terms of 5% significance level. Lastly, the trend slope
of each SPI and rainfall time series which referred to a significant change according
to modified Mann-Kendall test was obtained with linear regression. The slope values
for each model and location were also presented in Appendix B.
Figure 17 The study area with province names
53
In the mapping of the trend results, only the provinces covered in the study area were
visualized (Figure 17). A red or blue circle was fixed up depending on slope direction.
No circle was fixed up for the locations in which the significant trend was not
detected. Thus, all the circles in the maps were fixed up for only the locations where
a significant trend was detected and the results were interpreted noticing this
situation.
SPI 1
Trend analysis of successive SPI 1 values is important to detect changes in short term
drought as well as it is susceptible to seasonality effects. On the other hand,
examination of trends for this timescale is necessary to observe any tendency to
meteorological drought. Following paragraphs interpret the outcomes of trend
analysis results for SPI 1 showed in Figure 18. The legend indicated in Figure 18a is
valid for all SPI trend maps in the thesis.
Model 1-1 predicted negative slope in SPI 1 trendline for all the locations which
modified Mann-Kendall test detected significant change (Figure 18a). The
magnitudes of slopes were relatively greater on the points which are located in Muğla
and Adana provinces and western Antalya as well. Another model which is forced by
same GCM (model 1-2) predicted similar results to model 1-1 (Figure 18b). However,
Denizli is the only province which a significant trend was not detected for any
location according to model 1-1 while model 1-2 indicated no significant trend for
the locations in only Bursa province (Figures 18a and 18b).
Though both of the other two models (1-3 and 1-4) from ICHEC-EC-EARTH GCM
predicted only negative slope in SPI 1 trendlines, the geographical distribution of
significant changes is limited to a smaller area comparing to models 1-1 and 1-2
(Figures 18a, 18b, 18c and 18d). Modified Mann-Kendall test results depending on
model 1-3 predictions revealed no significant trend in SPI 1 values for Bursa,
54
Balıkesir and Osmaniye provinces and eastern Antalya (Figure 18c). Though the
trend result map of model 1-4 is like model 1-3 result map in terms of the locations
with highest drought increase trend, model 1-4 also projected negative slope in SPI 1
trendline for two provinces from northern part of study area -Balıkesir and Bursa
(Figure 18d).
The expected drought increase is considerably limited to a region according to models
forced by CNRM-CERFACS-CNRM-CM5 GCM (Figures 18e, 18f and 18g). Model
2-1 predicted negative slope for locations extending from western Antalya to İzmir
(Figure 18e). Still, there are three locations in which a drought increase was expected
from eastern part of study area -at least for one-monthly timescale. This model
predicted significant trend in SPI 1 values for none of the locations from Çanakkale,
Balıkesir and Adana provinces. On the other hand, there is one location in which
positive slope was detected from each of two provinces: Bursa and Mersin.
Model 2-2 predicted greater slope magnitude for the locations in which model 2-1
projected negative slope (Figure 18f). In addition to this, the location in which
drought decrease was expected from Bursa province is same with model 2-1, but
slope magnitude is smaller. Thus, it can be interpreted that model 2-2 predicted drier
conditions than model 2-1 predicted. Balıkesir and Adana are two common provinces
in which both models predicted no significant trend.
The area in which highest drought increase trends are likely to occur according to
model 2-3 is similar to model 2-1 and 2-2 (Figures 18e, 18f and 18g). This area
includes locations from Muğla province and western part of Antalya. However, this
model predicted negative slope in SPI 1 trendline for locations from Adana province
whereas other two models from same GCM did not predict significant trend. In
addition to this, no significant trend was detected for any location in Aydın province
as distinct from model 2-1 and 2-2 (Figures 18e, 18f, and 18g). The divergence of
these trend results for SPI 1 indicated the effect of RCA4 RCM which forces model
2-3 as well as a high probability of drought increase for certain parts of study area.
55
Model 3-1 predicted negative slope in SPI 1 trendline for locations from all provinces
covered in study area (Figure 18h). Particularly, the slope magnitudes are greater at
some locations from Muğla, Denizli, Burdur and Antalya provinces. The
geographical distribution of negative slope is relatively limited according to model
3-2 and the magnitudes are smaller (Figure 18i). This model did not predict any
significant trend for locations from Bursa province and northern parts of Çanakkale
and Balıkesir as well.
The drought increase trends are highest around Adana and Hatay provinces according
to model 3-3 (Figure 18j). There is no location in which model 3-3 predicted
significant trend from Aydın province like model 2-3 which is forced by same RCM:
RCA4.
Model 4-1 diverged from rest of the models owing to greater slope magnitudes that
all indicated a significant negative trend for SPI 1 (Figure 18k). Though, the highest
drought increase trends are around two regions (Muğla-Antalya and Adana-Hatay)
which are partially common with rest of the models (Figure 18). This model also
diverged from the other model couplings which are forced by same RCM (RCA4) in
terms of the wideness of significant trend locations (Figure 18d, 18g, 18j and 18k).
The other model 4-2 which is forced by same GCM (IPSL-IPSL-CM5A-MR) is the
only model that predicted positive slope in SPI 1 trendline for many locations (Figure
18l). Aegean coast -from Aydın to Çanakkale- is the part where drought decrease
expectations at its highest level. On the other side, negative slope was obtained in SPI
1 trendline for some locations from southern part of the study area which are common
with rest of the models (Figure 18).
56
Figure 18 The geographical distribution of trends for SPI 1. The legend is valid for
rest of the SPI trend maps
57
Figure 18. (cont’d)
58
Figure 18. (cont’d)
59
Figure 18. (cont’d)
60
Figure 18. (cont’d)
61
Figure 18. (cont’d)
62
Figure 18. (cont’d)
Considering the effect of GCMs by comparing the model couplings from same RCM
is also another aim of this study. There are three RCMs which coupled with different
GCMs: CCLM4-8-17, RACMO22E and RCA4 (Table 2). Model 1-2, 2-2 and 3-1 are
the models which are forced by CCLM4-8-17 RCM but different GCMs respectively:
ICHEC-EC-EARTH, CNRM-CERFACS-CNRM-CM5 and MOHC-HadGEM2-ES.
The number of significant trend detected locations according to model 2-2 which is
forced by CNRM-CERFACS-CNRM-CM5 GCM is less than model 1-2 and 3-1
detections (Figures 18b, 18f and 18h). The expected drought increase area is
relatively limited for model 2-3 in comparison to other models forced by RCA4 RCM
(Figures 18d, 18g, 18j, and 18k). On the other hand, the trend analysis maps of models
1-2 and 3-1 (forced by CCLM4-8-17 RCM) are similar to each other (Figure 18b and
18h). This similarity is also valid between models 1-3 and 3-2 (both forced by
RACMO22E RCM) and between models 1-4 and 3-3 (both forced by RCA4 RCM).
These matchings highlight the distinctness of CNRM-CERFACS-CNRM-CM5
GCM from other two GCMs (ICHEC-EC-EARTH and MOHC-HadGEM2-ES)
63
which were considered in this comparison. IPSL-IPSL-CM5A-MR is also a more
impact GCM since model 4-1 projects a quite wider drought increase area with
greater magnitudes than models 1-4, 2-3 and 3-3 predict which are forced by same
RCM: RCA4 (Figures 18d, 18g, 18j and 18k).
SPI 3
Significant trend in successive SPI 3 values can be interpreted a first step to
agricultural drought. In this part the trends in SPI 3 were interpreted comparing the
models and SPI 1 trend results.
Considering model 1-1, two different behavior on SPI trends occurred for the
locations in which a significant trend was detected for SPI 1 values (Figure 18a and
19a). Slope magnitudes became greater at this timescale for most of the locations in
which a negative slope was detected in SPI 1 trendline whereas significant trend did
not exist anymore for some of them. On the other hand, positive slope in SPI 3
trendline was detected for four locations from different provinces: Bursa, Balıkesir,
Antalya and Denizli. Still, the highest drought increase expectations according to SPI
3 trends are on the same area with SPI 1: Muğla, Antalya and Adana. This fact
indicated a tendency to agricultural drought increase.
Though significant trend disappeared for a few locations from northern Aegean coast,
rest of the locations in which a negative slope was estimated for SPI 1 signified a
greater magnitude for SPI 3 for model 1-2 (Figure 18b and 19b). This projection
pretty much fitted model 1-1 projection in terms of tendency to agricultural drought.
However, the drought increasing expectations became evident for a region from
western Antalya to İzmir and Mersin tend to live drier conditions rather than Adana
as a distinction from model 1-1 (Figures 19a and 19b).
64
There are new locations in which a significant trend (negative slope) for SPI 3 was
detected from southern part of the study area according to model 1-3 (Figure 19c).
Two locations from Manisa did not signify a significant trend at this timescale
anymore. The drought increase expectation aggregated around Muğla and western
Antalya according to this model considering the increasing slope magnitudes on
negative direction. Yet, the significant trend detected locations for SPI 3 are relatively
limited for model 1-3 in comparison to other models from same GCM (Figures 19a,
19b, 19c and 19d). This variation was also valid for SPI 1 trends (Figure 18a, Figure
18b, Figure 18c and Figure 18d).
Model 1-4 (Figure 19d) predicted greater slope magnitudes on negative direction for
SPI 3. The drought increase expectation is most likely for an area extending from
western Antalya to İzmir. Besides, there are new locations in which a significant trend
was detected from Mersin province.
The significant trend detected locations are even more limited for SPI 3 than SPI 1
according to model 2-1 (Figure 19e). However, the slope magnitudes increased on
both negative and positive directions comparing to SPI 1 (Figure 18e). This fact is
also valid for model 2-2 (Figure 18f and 19f). There is also one new location with
positive slope from Bursa province.
There is no location with significant trend on negative direction for SPI 3 from İzmir,
Denizli and Osmaniye provinces as distinct from SPI 1 for model 2-3 (Figure 18g
and 19g). This model predicted wetter conditions for southern Marmara considering
4 locations with positive slope from Çanakkale, Balıkesir and Bursa provinces.
Though, the negative slope magnitude increased for some locations from Muğla and
Gaziantep.
65
Figure 19. The geographical distribution of trends for SPI 3
66
Figure 19. (cont’d)
67
Figure 19. (cont’d)
68
Figure 19. (cont’d)
69
Figure 19. (cont’d)
70
Figure 19. (cont’d)
71
Model 3-1 (Figure 19h) predicted negative slope in SPI 3 trendlines for all provinces
except Bursa. The locations with greatest slope magnitudes are from Muğla, western
Antalya, Denizli, Hatay and Gaziantep at this timescale. The drought tendency is not
limited at meteorological level for almost whole study area according to this model.
The drought increasing expected locations shifted southernly according to model 3-
2 considering the differences between SPI 1 and SPI 3 (Figure 18f and 19f). Six
locations from Manisa, İzmir and Aegean coast of Balıkesir did not signify a negative
SPI slope at three-months timescale as well as new locations with negative slope
came out from Antalya, Mersin, Adana and Hatay provinces. Besides, a positive slope
was detected for four locations from southern Marmara.
The magnitudes of slopes in SPI 3 trendlines increased overall for model 3-3
projections comparing to SPI 1 (Figures 18j and 19j). Additionally, Manisa and
Denizli cover locations with negative slopes at this timescale. In general, the slope
magnitudes are close to each other for southern part of study area (along
Mediterranean coastline).
The geographical distributions of SPI 3 trend results are almost same with SPI 1 trend
results for model 4-1 and 4-2 (Figures 18k, 18l, 19k and 19l). However, the slopes
sharpened in both directions like rest of the models (Figure 18 and 19).
The regions in which drought expectations aggregated according to SPI 1 trendlines
(Muğla, western Antalya and Adana) keep this characteristic at SPI 3 as well (Figure
18 and 19). This fact can be interpreted as a transition from meteorological drought
to agricultural drought. However, the disappeared drought increasing signs for some
locations should be noticed (particularly for northern parts of the study area).
72
SPI 6
Considering the trendlines for SPI 6, the results of all models tend to predict drier
conditions for almost same areas with SPI 3 (Figures 19 and 20). However, all models
indicated greater slope magnitudes for both negative and positive directions. These
facts signify a tendency to hydrological drought for the locations which agricultural
drought increase likely to occur.
Muğla and western Antalya is the region which all models project drought increases
at 6-monthly timescale (Figure 20). Model 4-2 and three models (2-1, 2-2, 2-3) forced
by CNRM-CERFACS-CNRM-CM5 GCM diverged from rest of the models since
they do not predict drier conditions for Adana province as much as the others
predicted (Figures 20e, 20f, 20g and 20l). The northern parts of study area (Southern
Marmara) are likely not to live drier conditions at this timescale according to most of
the models. However, İzmir is the province which model projections did not fit each
other widely. Model 1-1, 1-2, 1-3, 1-4, 3-1, 3-2, 3-3 and 4-1 predicted a negative
slope in SPI 6 trendlines for more than one location from this province (Figure 20).
On the other hand, models 2-1 and 2-2 predicted drier conditions for only one location
from İzmir while models 2-3 and 4-2 did not predict negative slope for any location
in İzmir (Figures 20e, 20f, 20g and 20l).
73
Figure 20. The geographical distribution of trends for SPI 6
74
Figure 20. (cont’d)
75
Figure 20. (cont’d)
76
Figure 20. (cont’d)
77
Figure 20. (cont’d)
78
Figure 20. (cont’d)
79
SPI 9
Though the trend result maps for SPI 9 resembles SPI 6 result maps, there are some
locations which slope direction changed at this timescale (Figures 20 and 21).
There are seven new locations in which a significant trend was detected for SPI 9
according to model 1-2 (Figure 21b). All of them are from northern part of study area
-from Bursa, Balıkesir and Çanakkale provinces. One location from Bursa is likely
to live wetter conditions at this timescale whereas the rest are drier. The rest of the
trend result maps for SPI 9 did not change a lot from SPI 6 compared to model 1-1
and 1-2 (Figures 20a, 20b, 21a and 21b). Still, the sharpening slopes should be noticed
for these models.
Figure 21. The geographical distribution of trends for SPI 9
80
Figure 21. (cont’d)
81
Figure 21. (cont’d)
82
Figure 21. (cont’d)
83
Figure 21. (cont’d)
84
Figure 21. (cont’d)
85
Figure 21. (cont’d)
SPI 12
Evaluating trends in SPI 12 values is important since dryness for 12 months indicate
a serious tendency to hydrological drought. The geographical distribution of regions
which expected drier and wetter conditions aggregated for SPI 12 is same with SPI
9, SPI 6 and even SPI 3 (from Figure 19 to 22). Muğla and western Antalya is still
the most vulnerable region to drought increase whereas northern part of study area
(southern Marmara) is likely to live wetter conditions (Figure 22). However, trends
for different timescales are not persistent at some locations. Four locations from
Bursa and Çanakkale provinces which signaled a significant trend at negative slope
for SPI 9 disappeared at 12-monthly timescale according to model 1-2 (Figures 21b
and 22b).
86
Figure 22. The geographical distribution of trends for SPI 12
87
Figure 22. (cont’d)
88
Figure 22. (cont’d)
89
Figure 22. (cont’d)
90
Figure 22. (cont’d)
91
Figure 22. (cont’d)
92
İzmir should be separately discussed in terms of continuity of trends for proceeding
timescales. Models 1-1 and 3-2 predicted negative slope at fewer locations from İzmir
for SPI 12 than SPI 9 and model 2-1 vice versa (Figures 21a, 21i, 21e, 22a, 22i and
22e). This fact indicated a discrepancy between models for certain locations.
Annual Precipitation
Detecting trends in annual precipitation is another part of this study. Relations
between drought and rainfall amount can be examined owing to this analysis. In this
part, the geographical distribution of annual rainfall trends was discussed with trends
in SPI.
Model 1-1 (Figure 23a) predicted a decrease in annual rainfall for the locations which
are sensitive to drought increases according to SPI trends. Muğla and western Antalya
is the most sensitive region while a decreasing trend is valid along with whole
Mediterranean coast. However, neither rainfall decrease accompanied drought
increase at every location nor rainfall increase accompanied drought decrease at
every location (Figures 22a and 23a). Model 1-2 is like to model 1-1 in terms of
drought and rainfall trend consistency (Figures 22b and 23b). Nonetheless, annual
rainfall decrease expectations is more common according to model 1-2 projection.
Not only Mediterranean coast but also Aegean region is likely to receive less annual
precipitation.
Model 1-3 (Figure 23c) predicted annual rainfall decrease for a smaller area than most
of the models predicted. Muğla and western Antalya is the region which drought
increases almost followed rainfall decreases. The locations which are most likely to
receive less annual rainfall according to model 1-4 is same with rest of the models
(Figure 23). On the other hand, the vulnerable locations across entire study area like
model 1-2 (Figures 23b and 23d).
93
The parts of the study area which signaled trends in annual rainfall are almost same
for models 2-1, 2-2 and 2-3 which are forced by CNRM-CERFACS-CNRM-CM5
GCM (Figures 23e, 23f and 23g). These models predicted rainfall increase for at least
one location from Bursa province. In addition to this, few locations from Balıkesir
and Çanakkale are likely to receive more annual rainfall according to model 2-3
(Figure 23g). Model 3-1 predicted decrease in annual rainfall across the entire study
area like model 1-2, 1-4 and 4-1 (Figure 23). Model 1-2 is forced by same RCM
(CCLM4-8-17) with model 3-1 while models 1-4 and 4-1 are forced by RCA4 RCM.
Mediterranean coast is likely to receive less annual precipitation rather than Aegean
coast according to models 3-2 and 3-3 (Figures 23i and 23j). Additionally, drought
increase accompanied precipitation decrease in most of the locations for model
predictions discussed in this paragraph.
94
Figure 23. The geographical distribution of trends for annual rainfall
95
Figure 23. (cont’d)
96
Figure 23. (cont’d)
97
Figure 23. (cont’d)
98
Figure 23. (cont’d)
99
Figure 23. (cont’d)
100
Figure 23. (cont’d)
Model 4-1 predicted rainfall decrease for almost all locations like its predictions on
drought trends (Figure 23k). Model 4-2 (Figure 23l) diverged from rest of the models
considering its projections which signaled rainfall increase almost entire Aegean
coast and some other parts like eastern Antalya.
101
Changes in the Frequency of Drought Between the Mid and End of the
Century
Changes in intensity of drought were analyzed and mapped in this step of the study.
The projection period is divided into two periods: 1972-2050 and 2051-2100. Then,
the frequency of occurrence of three drought severity class (moderate, severe and
extreme) depending on SPI values was calculated through divided periods for 3 and
12 monthly scales. The proportion of frequencies was obtained at the final step as
shown in Eq. 17:
r =
o2
n2o1
n1
(17)
where, r is the ratio of frequencies for each drought severity class, o1 is number of
occurrences for a severity class within 1972-2050 period, o2 is the same as within
2051-2100 period, n1 and n2 are number of total months within each period.
In the mapping of the ratios, a base map prepared with provincial borders was
practiced. Though some provincial borders do not entirely fit to the study area since
they extend inner parts of the country, this mismatch was partly eliminated owing to
the implied interpolation method: Natural neighbor. This method was firstly
introduced by Sibson (1981), and ArcGIS software was used in practice of this study.
The limits at legends of the maps were constituted with the highest value of changes,
concerning demonstration of the divergence between models. The result maps were
presented in Figure 24.
The most significant result of this analysis is the frequency increase in the second
half of the century for severe and extreme droughts consistently for almost all models
and timescales (Figure 24). To clarify, the drought gets more often as the intensity
gets bigger. More frequent droughts are more possible for southern provinces, either.
102
The geographical distribution of ratios is consistent with trend analysis results.
Southern parts of study area are likely to occur more intense drought. Besides, the
geographical distribution of the ratios of frequency is quite homogeneous for SPI 3
compared to SPI 12 for all models. The highest ratios aggregate in certain parts of
study area (especially southwestern parts) considering changes in drought frequency
according to SPI 12 values. For example, the ratio exceeds 62 times for model 1-4
(Figure 24) under extreme drought severity condition considering SPI 12.
103
Fig
ure
24.
Changes
in t
he
freq
uency o
f dro
ug
ht. ‘
Mo
d’,
‘se
v’
and ‘
ext’
ind
icat
e m
oder
atel
y,
sever
ely
and e
xtr
em
ely
dry
cla
sses
res
pec
tively
.
104
Fig
ure
24.
(co
nt’
d)
105
Fig
ure
24.
(co
nt’
d)
106
Fig
ure
24
. (c
ont’
d)
107
Fig
ure
24.
(co
nt’
d)
108
Fig
ure
24.
(co
nt’
d)
109
Fig
ure
24.
(co
nt’
d)
110
Fig
ure
24.
(co
nt’
d)
111
Fig
ure
24.
(co
nt’
d)
112
Fig
ure
24.
(co
nt’
d)
113
Fig
ure
24.
(co
nt’
d)
114
Fig
ure
24.
(co
nt’
d)
115
Areal Extension of Drought within the Period
The plots in Figure 25 show the areal change of drought based on SPI severity
classes. The percentage of the locations at each month which is in relevant SPI value
interval for each class was calculated. Afterwards, the monthly averages were
obtained for 4 periods: 1971-2005, 2006-2040, 2041-2075, 2076-2099. SPI 3 values
were considered at this evaluation. The area under dry conditions is no more than
30% for the driest model (4-1), yet, the increase is related to intensity as the plots
indicated. For instance, extremely dry area does not exceed 6 % whereas the sharpest
increase is the case for this severity class.
Figure 25. The percentage of the stations under dry conditions
0
2
4
6
8
10
12
14
16
18
1-1 1-2 1-3 1-4 2-1 2-2 2-3 3-1 3-2 3-3 4-1 4-2
Per
cen
tage
of
the
stat
ion
s
a) Moderately dry
1972-2005 2006-2040 2041-2075 2076-2099
116
Figure 25. (cont’d)
0
2
4
6
8
10
12
14
16
18
1-1 1-2 1-3 1-4 2-1 2-2 2-3 3-1 3-2 3-3 4-1 4-2
Per
cen
tage
of
the
stat
ion
s
b) Severely dry
1972-2005 2006-2040 2041-2075 2076-2099
0
2
4
6
8
10
12
14
16
18
1-1 1-2 1-3 1-4 2-1 2-2 2-3 3-1 3-2 3-3 4-1 4-2
Per
cen
tage
of
the
stat
ion
s
c) Extremely dry
1972-2005 2006-2040 2041-2075 2076-2099
117
Figure 26. The average percentage of the stations under dry conditions for all models
Figure 26 indicates the percentages of stations under dry conditions by averaging
percentiles of 12 models. Though the percentages raised for all dryness classes, the
increase rates are diverse. While moderate dry locations raised from 7% to 11%,
percentages of severe and extreme dry locations raised almost 2 times (from 3% to
6% and from 1.5% to 4% respectively)
0
2
4
6
8
10
12
197
2-2
005
200
6-2
040
204
1-2
075
207
6-2
099
197
2-2
005
200
6-2
040
204
1-2
075
207
6-2
099
197
2-2
005
200
6-2
040
204
1-2
075
207
6-2
099
Moderate Severe Extreme
Perc
enta
ge o
f th
e locations
Model Mean
118
119
CHAPTER 4
SUMMARY, CONCLUSION AND RECOMMENDATIONS
In this thesis, Ensemble modeling approach was used to make predictions for drought
in the future of Turkey’s Mediterranean climate region. Observation and model
precipitation data were compared to measure the performance of each model within
the ensemble system. Afterwards, trends in drought depending on Standardized
Precipitation Index values and annual rainfall amounts were investigated.
Geographical distribution of trends was mapped. Frequency of different drought
severities was compared for two periods divided at half of 21st century. Areal
extension of drought severities was studied for 4 periods as well.
Models 1-4, 2-3 and 3-3 are distinguished from rest of the models with their high
consistency with observation data. It should be noticed that these models used the
same RCM (RCA4) but initiated with different GCMs. Additionally, RCM show
more impact on predictions considering the uncertainties that come from GCM and
RCM. Model 1-1 is also distinguished owing to its well correlation with observation
data considering daily means. Though, this model diverged from observation at 2 of
5 locations when annual rainfall trends were compared., Model 4-1 is another model
from RCA4 RCM that partially fitted observation though its underestimation remains
for entire year.
In case of projections, south of the study area (especially Muğla province and western
part of Antalya province) is the most sensitive region to drought in future according
to all model predictions. This result is consistent with other studies which
investigated drought trends in Turkey (Topcu et al., 2010; Sen et al., 2012). Hence,
120
the closeness of the results from all models for these regions indicated the consistency
of the models and the importance of drought signals. On the other hand, the variation
of the trend results of models for the rest of the area -especially along the Aegean
region- causes the necessity for evaluating the RCM projections more in detail in this
area. Most of the models project either no significant trend or wetter conditions for
locations from Çanakkale, Balıkesir and Bursa. Besides, the Marmara coast of these
provinces is likely to receive more precipitation.
Another significant result that can be inferred from both result tables and maps is the
increasing drought tendency for larger timescales. This means that the drier
conditions may not be limited to meteorological or agricultural scale. Increase in
hydrological drought is probable for most of the study area. Therefore, the
measurements that will be held to manage the effects of climate change should be
designed taking into account this projection outcome at this region.
The analyses revealed drought increase with decreasing trend at annual total
precipitation for most of the locations. Increase in drought may have a positive
correlation with decrease in annual precipitation in the region. However, the more
detailed drought and precipitation assessments considering the correlation between
these should be performed.
The increase in the frequency of different drought types based on SPI classification
is related to severity of class according to most of the models. This analysis result is
common with findings of Leng et al. (2015) on China. Areal extension proportions
of drought classes also consist with this result. Severely and extremely dry areas
extend more than moderately dry areas proportionally.
This thesis was dedicated to Mediterranean climate region of Turkey. The drought
analysis can be extended to entire Turkey. Other drought indices can also be implied.
Changes in temperature should also be studied to clarify the effect of climate change.
The relation between trends in drought and changes in seasonal distribution of
121
precipitation can be analyzed. The effects of climate change should be assessed via
analyzing the phenomena at larger scale as well. Poleward shift of Hadley cell is one
of these phenomena. Evaluating the trends in meteorological parameters on the belt
around 30° latitude will be useful to determine any significant change.
122
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WEB3: http://cordex.org/about/what-is-regional-downscaling/, last access:
December 9, 2017.
WEB4: https://www.mgm.gov.tr/veridegerlendirme/yagis-raporu.aspx#sfU, last
access: May 23, 2018.
WEB5: https://www.usatoday.com/story/weather/2015/08/19/california-drought-
cost-27-billion-2015/32007967/, last access: January 14, 2018.
WEB6: http://www.haberturk.com/kurak-gecen-kis-elektrik-fiyatlarinda-artisa-
neden-olacak-1789971-ekonomi, last access: January 14, 2018.
WEB7: http://drought.unl.edu/DroughtBasics/TypesofDrought.aspx, last access:
January 14, 2018.
WEB8: http://vlscop.vermontlaw.edu/2016/11/16/implementing-adaptation-for-
resilient-mediterranean-climate-regions/, last access: May 23, 2018.
WEB9: http://www.eba.gov.tr/dokuman/353?icerik-
id=3798f6b4aca17c4e040f9870262671cec553ddfbde001&channel=60, last
access: January 24, 2018.
WEB10: https://portal.enes.org/data/enes-model-data/cordex/datastructure, last
access: January 24, 2018.
Wilhite, D. (1985). Understanding the Drought Phenomenon: The Role of
Definitions, (August 2013), 37–41.
126
APPENDICES
A. MATLAB CODES
MATLAB code for Modified Mann-Kendall Test (prepared by Simone Fatichi)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%% MANN-KENDALL TEST MODIFIED by Hamed and Rao, (1998) %%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function[H,p_value]=Mann_Kendall_Modified(V,alpha)
%%%%%%%%%%%%%%%%%
%%% Performs Mann-Kendall test modified to account for autocorrelation on
the time series
%%% The null hypothesis of trend
%%% absence in the vector V is tested, against the alternative of trend.
%%% The result of the test is returned in H = 1 indicates
%%% a rejection of the null hypothesis at the alpha significance level. H
= 0 indicates
%%% a failure to reject the null hypothesis at the alpha significance
level.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% INPUTS
%V = time series [vector]
%alpha = significance level of the test [scalar]
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% From Matlab Help %%%%%%%%%%%%%%%
%The significance level of a test is a threshold of probability a agreed
%to before the test is conducted. A typical value of alpha is 0.05. If the
p-value of a test is less than alpha,
%the test rejects the null hypothesis. If the p-value is greater than
alpha, there is insufficient evidence
%to reject the null hypothesis.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% OUTPUTS
127
%H = test result [1] Reject of Null Hypthesis [0] Insufficient evidence to
reject the null hypothesis
%p_value = p-value of the test
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% From Matlab Help %%%%%%%%%%%%%%%
%The p-value of a test is the probability, under the null hypothesis, of
obtaining a value
%of the test statistic as extreme or more extreme than the value computed
from
%the sample.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%% References
%Mann, H. B. (1945), Nonparametric tests against trend, Econometrica, 13,
%245 259.
%Kendall, M. G. (1975), Rank Correlation Methods, Griffin, London.
%Hamed, K. H., and A. R. Rao (1998), A modified Mann-Kendall trend test
%for autocorrelated data, J. Hydrol., 204, 182196.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Simone Fatichi -- [email protected]
% Copyright 2009
% $Date: 2009/10/03 $
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
V=reshape(V,length(V),1);
alpha = alpha/2; %
n=length(V);
i=0; j=0; S=0;
for i=1:n-1
for j= i+1:n
S= S + sign(V(j)-V(i));
end
end
VarSo=(n*(n-1)*(2*n+5))/18;
%%%%%%%%%%%%%%%%%%%%%%%%
ANSW = 3; %%% It depends on computational time
switch ANSW
case 1
xx=1:n;
aa=polyfit(xx,V,1);
yy=aa(1,1)*xx+aa(1,2);
V=V-yy';
case 2
[b]=Sen_Slope(V);
128
xx=1:n;
yy=b*xx+ (mean(V) -(b*n)/2);
V=V-yy';
case 3
V=detrend(V);
end
%%%%%%%%%%%%%%%%%%%%%%%%%
[V,I]=sort(V); %% I = ranks
[Acx,lags,Bounds]=autocorr(I,n-1);
%[Acx,lags]=xcov(I,I,n-1,'coeff'); %%
%Acx=Acx(n:end);
ros=Acx(2:end); %% Autocorrelation Ranks
i=0; sni=0;
for i=1:n-2
if ros(i)<= Bounds(1) andand ros(i) >= Bounds(2)
sni=sni;
else
sni=sni+(n-i)*(n-i-1)*(n-i-2)*ros(i);
end
end
nns=1+(2/(n*(n-1)*(n-2)))*sni;
VarS=VarSo*(nns);
StdS=sqrt(VarS);
if S >= 0
Z=((S-1)/StdS)*(S~=0);
else
Z=(S+1)/StdS;
end
p_value=2*(1-normcdf(abs(Z),0,1));
pz=norminv(1-alpha,0,1);
H=abs(Z)>pz; %
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%% Trend Magnitude ---> Sen (1968)%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function[b]=Sen_Slope(X)
i=0; %
n=length(X);
V= zeros(1,(n^2-n)/2);
for j=2:n
for l=1:j-1
i=i+1;
129
V(i)=(X(j)-X(l))/(j-l);
end
end
b=median(V);
end
130
MATLAB code for Standardized Precipitation Index (prepared by Taesam Lee)
%%
% Programmed by Taesam Lee, Dec.03,2009
% INRS-ETE, Quebec, Canada
function [Z]=SPI(Data,scale,nseas)
%Standardized Precipitation Index
% Input Data
% Data : Monthly Data vector not matrix (monthly or seasonal
precipitation)
% scale : 1,3,12,48
% nseas : number of season (monthly=12)
% Example
% Z=SPI(gamrnd(1,1,1000,1),3,12); 3-monthly scale,
% Notice that the rest of the months of the fist year are removed.
% eg. if scale =3, fist year data 3-12 SPI values are not estimated.
%if row vector then make coloumn vector
%if (sz==1) Data(:,1)=Data;end
erase_yr=ceil(scale/12);
% Data setting to scaled dataset
A1=[];
for is=1:scale, A1=[A1,Data(is:length(Data)-scale+is)];end
XS=sum(A1,2);
if(scale>1), XS(1:nseas*erase_yr-scale+1)=[]; end
for is=1:nseas
tind=is:nseas:length(XS);
Xn=XS(tind);
[zeroa]=find(Xn==0);
Xn_nozero=Xn;Xn_nozero(zeroa)=[];
q=length(zeroa)/length(Xn);
parm=gamfit(Xn_nozero);
Gam_xs=q+(1-q)*gamcdf(Xn,parm(1),parm(2));
Z(tind)=norminv(Gam_xs);
end
%Gamma parameter estimation and tranform
131
B. TREND SLOPE TABLES
Table 11. Trend slope values for model 1-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - 0.0001 0.0003 0.0004 0.0004 0.7152
AYVALIK - - 0.0001 0.0002 0.0002 -
DİKİLİ -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -0.7359
AKHİSAR -0.0002 - - - - -
KUŞADASI -0.0002 -0.0003 - - - -
DİDİM -0.0003 -0.0004 -0.0003 -0.0003 -0.0003 -0.6720
BODRUM -0.0003 -0.0003 -0.0003 -0.0003 -0.0003 -0.8070
DALAMAN -0.0004 -0.0005 -0.0005 -0.0006 -0.0006 -2.9368
ANAMUR -0.0003 -0.0004 -0.0006 -0.0007 -0.0007 -1.9160
SİLİFKE -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -0.8126
İSKENDERUN - - - - - -
FİNİKE -0.0004 -0.0006 -0.0009 -0.0010 -0.0010 -6.2084
KAŞ -0.0003 -0.0006 -0.0008 -0.0010 -0.0010 -2.7616
SALİHLİ -0.0001 - - 0.0002 0.0002 -
SEFERİHİSAR -0.0002 - - - - -
ÖDEMİŞ -0.0003 -0.0003 -0.0002 -0.0002 -0.0002 -
NAZİLLİ - - - - - -
ELMALI - 0.0003 0.0005 0.0007 0.0007 0.2513
MUT -0.0001 - - - - -
KARATAŞ -0.0003 -0.0005 -0.0006 -0.0007 -0.0007 -1.2930
MENEMEN -0.0003 -0.0003 -0.0002 - - -
FETHİYE -0.0003 -0.0005 -0.0006 -0.0007 -0.0007 -1.7236
MARMARİS -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -0.9714
BURHANİYE -0.0002 - - - - -
MİLAS -0.0002 -0.0003 -0.0002 -0.0002 -0.0002 -
YATAĞAN -0.0002 - - - - -
KOZAN -0.0003 -0.0005 -0.0005 -0.0006 -0.0006 -1.6484
132
Table 11. (cont’d) Trend slope values for model 1-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
DATÇA -0.0004 -0.0006 -0.0008 -0.0009 -0.0009 -3.2641
KÖYCEĞİZ -0.0003 -0.0004 -0.0004 -0.0004 -0.0004 -1.5417
KORKUTELİ -0.0003 -0.0005 -0.0006 -0.0007 -0.0007 -1.4587
KARAİSALI -0.0003 -0.0005 -0.0007 -0.0008 -0.0008 -1.6726
MANAVGAT -0.0002 -0.0004 -0.0005 -0.0006 -0.0006 -2.3695
ERDEMLİ -0.0002 -0.0004 -0.0006 -0.0007 -0.0007 -1.0295
CEYHAN -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.0131
DÖRTYOL - - -0.0003 -0.0004 -0.0004 -1.2068
ISLAHİYE -0.0002 -0.0002 -0.0003 -0.0003 -0.0003 -1.0821
GAZİPAŞA -0.0002 -0.0004 -0.0005 -0.0005 -0.0005 -1.9558
YUMURTALIK -0.0003 -0.0004 -0.0003 -0.0004 -0.0004 -1.1646
SAMANDAĞ -0.0002 -0.0004 -0.0005 -0.0006 -0.0006 -1.7947
ACIPAYAM - 0.0002 0.0004 0.0005 0.0005 0.2864
TEFENNİ -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -0.2395
GEMLİK - - - - - -
KARACABEY - - - - - -
MUDANYA - 0.0001 0.0003 0.0004 0.0004 0.6982
M.KEMALPAŞA - - - - - -
AYVACIK -0.0002 -0.0004 -0.0004 -0.0005 -0.0005 -1.2531
OSMANIYE -0.0001 -0.0002 -0.0003 -0.0004 -0.0004 -0.5273
ALANYA -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -1.9989
MANISA -0.0002 - - - - -
IZMIR -0.0002 -0.0002 -0.0002 - - -
AYDIN -0.0002 -0.0002 - - - -
DENIZLI - - 0.0003 0.0005 0.0005 0.5198
MUGLA -0.0004 -0.0006 -0.0007 -0.0008 -0.0008 -4.6311
ANTALYA -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.9478
MERSIN -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.0536
ADANA -0.0003 -0.0005 -0.0006 -0.0007 -0.0007 -1.1703
ANTAKYA -0.0003 -0.0004 -0.0004 -0.0005 -0.0005 -0.6076
BALIKESİR -0.0001 - - - - -
CANAKKALE -0.0001 - - - - -
BURSA -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -1.6586
133
Table 12. Trend slope values for model 1-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - - 0.0000 - -
AYVALIK -0.0002 - - -0.0004 - -0.7978
DİKİLİ -0.0002 -0.0003 -0.0003 -0.0003 - -
AKHİSAR -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -0.8166
KUŞADASI -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.1836
DİDİM -0.0002 -0.0005 -0.0006 -0.0007 -0.0007 -1.2741
BODRUM -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.2539
DALAMAN -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -2.1662
ANAMUR -0.0002 -0.0004 -0.0006 -0.0007 -0.0007 -2.0738
SİLİFKE -0.0003 -0.0005 -0.0006 -0.0008 -0.0009 -1.8544
İSKENDERUN -0.0003 -0.0004 -0.0004 -0.0005 -0.0006 -0.8768
FİNİKE -0.0003 -0.0005 -0.0007 -0.0009 -0.0009 -3.2208
KAŞ -0.0003 -0.0005 -0.0007 -0.0008 -0.0009 -2.2175
SALİHLİ -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.1015
SEFERİHİSAR -0.0002 -0.0004 -0.0005 -0.0005 -0.0006 -0.7468
ÖDEMİŞ -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.3725
NAZİLLİ -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.0521
ELMALI -0.0005 -0.0007 -0.0010 -0.0011 -0.0012 -2.1464
MUT -0.0003 -0.0006 -0.0007 -0.0008 -0.0009 -1.1675
KARATAŞ -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -0.8206
MENEMEN -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -0.9390
FETHİYE -0.0003 -0.0005 -0.0005 -0.0006 -0.0007 -2.0024
MARMARİS -0.0003 -0.0005 -0.0007 -0.0008 -0.0008 -2.4706
BURHANİYE -0.0002 - - -0.0004 - -
MİLAS -0.0003 -0.0005 -0.0007 -0.0008 -0.0009 -1.6289
YATAĞAN -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -1.7983
KOZAN -0.0001 -0.0002 - -0.0003 - -
DATÇA -0.0003 -0.0005 -0.0007 -0.0008 -0.0008 -1.2993
KÖYCEĞİZ -0.0003 -0.0006 -0.0008 -0.0009 -0.0010 -2.6385
KORKUTELİ -0.0005 -0.0008 -0.0010 -0.0012 -0.0013 -2.6246
KARAİSALI -0.0002 -0.0003 -0.0005 -0.0005 -0.0006 -1.7505
MANAVGAT -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -1.5245
ERDEMLİ -0.0002 -0.0004 -0.0005 -0.0006 -0.0007 -1.5895
134
Table 12. (cont’d) Trend slope values for model 1-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0001 -0.0002 -0.0003 -0.0003 -0.0003 -
DÖRTYOL -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.2645
ISLAHİYE -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.0859
GAZİPAŞA - -0.0003 -0.0004 -0.0004 -0.0004 -1.1386
YUMURTALIK -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -
SAMANDAĞ -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -
ACIPAYAM -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -1.2656
TEFENNİ -0.0004 -0.0006 -0.0008 -0.0010 -0.0011 -1.5683
GEMLİK - - - 0.0001 - -
KARACABEY - - - -0.0001 - -
MUDANYA - - - 0.0002 0.0003 -
M.KEMALPAŞA - - - -0.0001 - -
AYVACIK -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -0.8111
OSMANIYE -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.9943
ALANYA -0.0002 -0.0004 -0.0005 -0.0005 -0.0006 -1.7941
MANISA -0.0003 -0.0005 -0.0006 -0.0007 -0.0007 -1.0241
IZMIR -0.0003 -0.0005 -0.0006 -0.0007 -0.0007 -1.2277
AYDIN -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.2547
DENIZLI -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.0201
MUGLA -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -2.5862
ANTALYA -0.0002 -0.0004 -0.0006 -0.0007 -0.0008 -3.9625
MERSIN -0.0002 -0.0004 -0.0005 -0.0006 -0.0007 -1.7131
ADANA -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.8752
ANTAKYA -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -0.9184
BALIKESİR -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -0.6535
CANAKKALE -0.0002 - - -0.0002 - -
BURSA - - - 0.0000 - -
135
Table 13. Trend slope values for model 1-3
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - - - - -
AYVALIK - - - - - -
DİKİLİ - - - - - -
AKHİSAR -0.0001 - - - - -
KUŞADASI -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -0.9031
DİDİM -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.9960
BODRUM -0.0002 -0.0004 -0.0005 -0.0006 -0.0007 -1.4405
DALAMAN -0.0002 -0.0004 -0.0005 -0.0006 -0.0006 -1.8145
ANAMUR - -0.0002 -0.0003 -0.0003 -0.0004 -
SİLİFKE -0.0002 -0.0003 -0.0004 -0.0004 -0.0004 -0.8435
İSKENDERUN - - - - - -
FİNİKE -0.0003 -0.0005 -0.0007 -0.0008 -0.0009 -3.2487
KAŞ -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -2.2196
SALİHLİ -0.0002 -0.0002 - - - -
SEFERİHİSAR -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -0.4410
ÖDEMİŞ -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -0.8051
NAZİLLİ -0.0001 -0.0002 -0.0002 -0.0002 - -
ELMALI -0.0003 -0.0005 -0.0005 -0.0006 -0.0007 -0.8198
MUT -0.0001 -0.0002 - - - -
KARATAŞ -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -0.7611
MENEMEN -0.0001 -0.0002 - - - -
FETHİYE -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -1.1707
MARMARİS -0.0003 -0.0005 -0.0007 -0.0008 -0.0008 -2.7955
BURHANİYE - - - - - -
MİLAS -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.0603
YATAĞAN -0.0002 -0.0003 -0.0004 -0.0004 -0.0004 -0.7799
KOZAN - - - - -0.0002 -
DATÇA -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.5281
KÖYCEĞİZ -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -2.2773
KORKUTELİ -0.0004 -0.0005 -0.0007 -0.0007 -0.0008 -1.8245
KARAİSALI - -0.0002 -0.0002 -0.0003 -0.0003 -0.6273
MANAVGAT - -0.0002 -0.0003 -0.0003 -0.0003 -1.0409
ERDEMLİ - - - -0.0001 - -
136
Table 13. (cont’d) Trend slope values for model 1-3
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0002 -0.0002 -0.0002 -0.0002 -0.0003 -
DÖRTYOL - - - - - -
ISLAHİYE -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -0.7705
GAZİPAŞA - -0.0002 -0.0002 - - -
YUMURTALIK - - - - - -
SAMANDAĞ -0.0001 -0.0002 -0.0002 -0.0002 - -
ACIPAYAM -0.0002 -0.0003 -0.0004 -0.0004 -0.0004 -0.3892
TEFENNİ -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.3714
GEMLİK - - 0.0002 0.0003 0.0003 -
KARACABEY - - - - - -
MUDANYA - - 0.0003 0.0004 0.0004 0.6907
M.KEMALPAŞA - - - - - -
AYVACIK -0.0001 -0.0002 - - -0.0002 -
OSMANIYE - - - - - -
ALANYA - - -0.0002 -0.0003 -0.0003 -
MANISA -0.0001 - - - - -
IZMIR -0.0002 -0.0002 -0.0002 - - -
AYDIN -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -
DENIZLI -0.0001 -0.0002 - - - -
MUGLA -0.0003 -0.0005 -0.0006 -0.0006 -0.0007 -2.6603
ANTALYA -0.0002 -0.0003 -0.0005 -0.0005 -0.0006 -2.5428
MERSIN - -0.0001 -0.0002 -0.0003 -0.0003 -0.6400
ADANA -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -0.7370
ANTAKYA - -0.0002 -0.0002 - - -
BALIKESİR - - - - - -
CANAKKALE - - - - - -
BURSA - - - - - -
137
Table 14. Trend slope values for model 1-4
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - - - - -
AYVALIK -0.0002 -0.0003 -0.0003 -0.0003 -0.0003 -
DİKİLİ -0.0002 -0.0002 -0.0002 - - -
AKHİSAR - -0.0003 -0.0003 -0.0003 -0.0003 -
KUŞADASI -0.0003 -0.0005 -0.0005 -0.0006 -0.0006 -1.0224
DİDİM -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.4823
BODRUM -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.3338
DALAMAN -0.0003 -0.0006 -0.0007 -0.0008 -0.0009 -2.8391
ANAMUR -0.0001 -0.0003 -0.0004 -0.0005 -0.0006 -0.9105
SİLİFKE - -0.0002 -0.0003 -0.0004 -0.0004 -0.6056
İSKENDERUN -0.0001 - - - - -
FİNİKE -0.0004 -0.0007 -0.0009 -0.0011 -0.0012 -3.6544
KAŞ -0.0003 -0.0006 -0.0008 -0.0009 -0.0010 -2.2666
SALİHLİ -0.0003 -0.0005 -0.0007 -0.0008 -0.0009 -0.9584
SEFERİHİSAR - -0.0004 -0.0005 -0.0005 -0.0006 -0.4760
ÖDEMİŞ -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -0.8065
NAZİLLİ - -0.0005 -0.0006 -0.0006 -0.0007 -0.4756
ELMALI - -0.0004 -0.0005 -0.0005 -0.0006 -0.3239
MUT - -0.0002 -0.0002 - - -
KARATAŞ -0.0001 -0.0002 -0.0003 -0.0003 -0.0004 -0.7029
MENEMEN -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -1.0610
FETHİYE -0.0003 -0.0005 -0.0007 -0.0007 -0.0008 -1.8234
MARMARİS -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -2.6772
BURHANİYE - -0.0003 -0.0003 -0.0003 -0.0003 -
MİLAS - -0.0004 -0.0005 -0.0005 -0.0006 -0.8210
YATAĞAN - -0.0006 -0.0007 -0.0008 -0.0009 -0.9778
KOZAN -0.0001 -0.0002 - - - -
DATÇA -0.0004 -0.0007 -0.0009 -0.0011 -0.0012 -3.9260
KÖYCEĞİZ - -0.0005 -0.0007 -0.0007 -0.0008 -1.9815
KORKUTELİ -0.0003 -0.0005 -0.0006 -0.0008 -0.0009 -2.1072
KARAİSALI -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -0.9432
MANAVGAT -0.0002 -0.0003 -0.0004 -0.0004 -0.0004 -1.4669
ERDEMLİ -0.0001 -0.0002 -0.0003 -0.0004 -0.0005 -0.5452
138
Table 14. (cont’d) Trend slope values for model 1-4
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0002 - -0.0003 -0.0003 - -
DÖRTYOL - - - - - -
ISLAHİYE -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.7000
GAZİPAŞA -0.0001 -0.0002 - - - -
YUMURTALIK -0.0001 - - - - -
SAMANDAĞ -0.0001 - -0.0003 - - -
ACIPAYAM -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -0.4870
TEFENNİ -0.0003 -0.0005 -0.0006 -0.0006 -0.0007 -0.7070
GEMLİK -0.0001 - - - - -
KARACABEY - - - - - -
MUDANYA - - - - - -
M.KEMALPAŞA -0.0001 -0.0001 - - - -
AYVACIK -0.0003 -0.0005 -0.0005 -0.0006 -0.0007 -1.6756
OSMANIYE - - - - - -
ALANYA -0.0001 -0.0003 -0.0003 -0.0003 -0.0004 -
MANISA - -0.0004 -0.0006 -0.0007 -0.0007 -0.6581
IZMIR -0.0003 -0.0004 -0.0005 -0.0005 -0.0005 -0.8163
AYDIN - -0.0004 -0.0005 -0.0005 -0.0006 -0.7465
DENIZLI -0.0003 -0.0005 -0.0006 -0.0006 -0.0007 -0.5057
MUGLA -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -3.3837
ANTALYA -0.0003 -0.0006 -0.0007 -0.0008 -0.0009 -2.3454
MERSIN - -0.0002 -0.0003 -0.0004 -0.0004 -0.5228
ADANA -0.0002 -0.0002 -0.0003 - - -0.6302
ANTAKYA -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -0.3788
BALIKESİR -0.0002 -0.0002 - - - -
CANAKKALE -0.0002 -0.0003 - - - -
BURSA -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -1.1386
139
Table 15. Trend slope values for model 2-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - - - - -
AYVALIK - - - - - -
DİKİLİ - - - - - -
AKHİSAR -0.0002 -0.0002 - - - -
KUŞADASI -0.0002 - - - - -
DİDİM -0.0001 - - - - -
BODRUM -0.0001 - - - - -0.4787
DALAMAN -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -0.7803
ANAMUR -0.0001 -0.0002 -0.0004 -0.0005 -0.0005 -1.1723
SİLİFKE - - -0.0002 -0.0002 -0.0003 -
İSKENDERUN - - - - - -
FİNİKE - - - - - -
KAŞ -0.0002 -0.0004 -0.0006 -0.0008 -0.0009 -1.8069
SALİHLİ -0.0001 - - - - -
SEFERİHİSAR - - - - - -
ÖDEMİŞ -0.0003 -0.0004 -0.0005 -0.0007 -0.0007 -1.4170
NAZİLLİ -0.0001 - - - - -
ELMALI -0.0002 -0.0003 -0.0005 -0.0006 -0.0007 -0.8330
MUT - - - - - -
KARATAŞ - - - - - -
MENEMEN -0.0001 - - - -0.0003 -
FETHİYE -0.0002 -0.0004 -0.0005 -0.0007 -0.0007 -1.0119
MARMARİS -0.0002 -0.0002 -0.0003 -0.0004 -0.0005 -1.3780
BURHANİYE - - - - - -
MİLAS -0.0002 -0.0002 -0.0003 -0.0004 -0.0004 -0.5783
YATAĞAN -0.0001 - - - - -
KOZAN - - - - - -
DATÇA -0.0001 - - - - -
KÖYCEĞİZ -0.0003 -0.0004 -0.0006 -0.0007 -0.0008 -1.2032
KORKUTELİ - - - - - -
KARAİSALI - - - -0.0003 -0.0003 -
MANAVGAT - - - - - -0.6980
ERDEMLİ - - - -0.0003 -0.0004 -
140
Table 15. (cont’d) Trend slope values for model 2-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN - - - - - -
DÖRTYOL -0.0001 -0.0002 -0.0003 -0.0003 -0.0004 -0.3883
ISLAHİYE -0.0001 -0.0002 - -0.0003 -0.0003 -
GAZİPAŞA - - - - - -
YUMURTALIK - - 0.0002 0.0002 0.0003 -
SAMANDAĞ - 0.0002 0.0003 0.0004 0.0005 1.9858
ACIPAYAM -0.0002 -0.0002 - - - -
TEFENNİ -0.0002 - - - - -0.4306
GEMLİK - - - - - -
KARACABEY - - - - - -
MUDANYA 0.0002 0.0004 0.0007 0.0008 0.0009 2.4122
M.KEMALPAŞA - - - - - -
AYVACIK - - - - - -0.5220
OSMANIYE -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -0.5156
ALANYA - - - - - -
MANISA - - - - - -
IZMIR - - - - - -
AYDIN -0.0002 -0.0002 -0.0003 -0.0003 -0.0003 -0.4104
DENIZLI -0.0001 - - - - -
MUGLA -0.0003 -0.0005 -0.0006 -0.0008 -0.0009 -2.6566
ANTALYA -0.0002 -0.0004 -0.0005 -0.0007 -0.0007 -1.5869
MERSIN 0.0001 0.0002 0.0003 0.0004 0.0004 0.6073
ADANA - - - - - -
ANTAKYA - - - - - -
BALIKESİR - - - - - -
CANAKKALE - - - - - -
BURSA - - - - - -
141
Table 16. Trend slope values for model 2-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - 0.0002 0.0003 0.0003 0.4893
AYVALIK - - 0.0002 0.0002 0.0002 -
DİKİLİ - - - - 0.0002 -
AKHİSAR - - - - - -
KUŞADASI -0.0001 - - - - -
DİDİM - - - - - -
BODRUM -0.0001 - -0.0001 - - -
DALAMAN -0.0001 -0.0001 -0.0002 - - -
ANAMUR -0.0001 -0.0002 -0.0002 -0.0002 -0.0003 -
SİLİFKE -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -1.4521
İSKENDERUN -0.0002 -0.0002 -0.0003 -0.0004 -0.0004 -0.7100
FİNİKE -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -2.0834
KAŞ -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.4103
SALİHLİ -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -
SEFERİHİSAR -0.0001 - - - - -
ÖDEMİŞ -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.1444
NAZİLLİ -0.0002 -0.0002 -0.0003 -0.0004 -0.0004 -0.9157
ELMALI -0.0004 -0.0006 -0.0007 -0.0009 -0.0010 -1.8405
MUT -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.1899
KARATAŞ - - - - - -
MENEMEN -0.0001 - - - - -
FETHİYE -0.0001 -0.0002 -0.0002 -0.0002 -0.0003 -1.1177
MARMARİS -0.0001 -0.0002 -0.0002 - - -
BURHANİYE - - - - - -
MİLAS -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -1.1883
YATAĞAN -0.0003 -0.0004 -0.0006 -0.0007 -0.0008 -1.7752
KOZAN - - - - - -
DATÇA -0.0001 -0.0001 - - - -
KÖYCEĞİZ -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -2.2099
KORKUTELİ -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -2.1082
KARAİSALI - - - - - -
MANAVGAT - - - - - -
ERDEMLİ -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -
142
Table 16. (cont’d) Trend slope values for model 2-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN - - - - - -
DÖRTYOL -0.0002 -0.0002 -0.0002 -0.0003 -0.0003 -0.7822
ISLAHİYE -0.0003 -0.0004 -0.0004 -0.0005 -0.0006 -1.0588
GAZİPAŞA - - - - - -
YUMURTALIK - - - - - -
SAMANDAĞ -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -0.9092
ACIPAYAM -0.0004 -0.0005 -0.0007 -0.0008 -0.0009 -1.4951
TEFENNİ -0.0004 -0.0005 -0.0006 -0.0008 -0.0009 -1.3775
GEMLİK - 0.0002 0.0003 0.0004 0.0004 0.8583
KARACABEY - - 0.0003 0.0004 0.0004 0.7794
MUDANYA 0.0002 0.0003 0.0005 0.0006 0.0007 1.5519
M.KEMALPAŞA - - 0.0003 0.0003 0.0004 0.7508
AYVACIK -0.0001 -0.0001 -0.0002 -0.0002 -0.0002 -
OSMANIYE - -0.0001 -0.0002 -0.0002 - -
ALANYA -0.0001 - - - - -
MANISA -0.0001 - - - - -
IZMIR -0.0001 -0.0002 - - - -
AYDIN -0.0002 -0.0002 -0.0002 -0.0002 -0.0003 -
DENIZLI -0.0003 -0.0004 -0.0006 -0.0007 -0.0008 -1.4013
MUGLA -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -2.3274
ANTALYA -0.0002 -0.0002 -0.0003 -0.0004 -0.0004 -2.9119
MERSIN - - - - - -
ADANA - - - - - -
ANTAKYA -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.7609
BALIKESİR - - - - - -
CANAKKALE - - - - - -
BURSA - - - - - -
143
Table 17. Trend slope values for model 2-3
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA 0.0001 0.0002 0.0004 0.0005 0.0006 0.8874
AYVALIK - - 0.0001 0.0002 0.0002 -
DİKİLİ - - - - - -
AKHİSAR - - - - - -
KUŞADASI - - - - - -
DİDİM - - - - - -
BODRUM -0.0001 -0.0001 - - - -
DALAMAN -0.0002 -0.0002 -0.0003 -0.0003 -0.0003 -1.4235
ANAMUR - -0.0001 - - -0.0003 -
SİLİFKE -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.0499
İSKENDERUN -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -0.7376
FİNİKE -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.4041
KAŞ -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.0963
SALİHLİ -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -0.4387
SEFERİHİSAR -0.0001 - - - - -
ÖDEMİŞ - - - - - -
NAZİLLİ - - - - - -
ELMALI - - - - - -
MUT - -0.0002 -0.0002 -0.0003 -0.0004 -0.3133
KARATAŞ -0.0001 - - - - -
MENEMEN -0.0001 - - - - -
FETHİYE -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.2153
MARMARİS -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -1.4218
BURHANİYE - -0.0001 - -0.0002 - -
MİLAS -0.0001 -0.0002 -0.0002 -0.0003 - -0.6283
YATAĞAN -0.0002 -0.0003 -0.0005 -0.0006 -0.0006 -0.9051
KOZAN -0.0001 - - - - -
DATÇA -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -1.3057
KÖYCEĞİZ -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.7555
KORKUTELİ -0.0002 -0.0002 -0.0003 -0.0004 -0.0004 -
KARAİSALI -0.0001 -0.0001 -0.0002 -0.0003 -0.0003 -
MANAVGAT -0.0001 - - -0.0003 -0.0003 -1.4126
ERDEMLİ -0.0001 -0.0002 -0.0003 -0.0004 -0.0005 -0.7625
144
Table 17. (cont’d) Trend slope values for model 2-3
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0001 -0.0001 - - - -
DÖRTYOL - - - -0.0002 -0.0003 -
ISLAHİYE -0.0003 -0.0005 -0.0005 -0.0006 -0.0007 -1.8122
GAZİPAŞA - - - - - -
YUMURTALIK -0.0001 - - - - -
SAMANDAĞ -0.0002 -0.0002 -0.0003 -0.0003 -0.0003 -0.8575
ACIPAYAM -0.0001 - - - - -
TEFENNİ -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.5122
GEMLİK - - - - - -
KARACABEY - 0.0002 0.0004 0.0005 0.0006 0.6831
MUDANYA - - - 0.0004 0.0004 -
M.KEMALPAŞA - 0.0001 0.0002 0.0003 0.0004 -
AYVACIK - - - - - -
OSMANIYE -0.0001 - - - - -
ALANYA -0.0001 - -0.0002 -0.0003 -0.0004 -1.4152
MANISA -0.0001 -0.0002 -0.0002 -0.0003 -0.0003 -0.3649
IZMIR -0.0001 - - -0.0002 -0.0003 -0.5513
AYDIN - - - - - -
DENIZLI -0.0001 - - - - -0.2599
MUGLA -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -3.0774
ANTALYA -0.0002 -0.0002 -0.0002 -0.0003 -0.0004 -0.9998
MERSIN -0.0001 - -0.0002 -0.0003 -0.0004 -
ADANA -0.0002 -0.0001 -0.0001 - - -
ANTAKYA -0.0002 -0.0002 -0.0004 -0.0005 -0.0005 -0.4665
BALIKESİR - - - - - -
CANAKKALE - 0.0002 0.0003 0.0003 0.0004 0.5070
BURSA - - - - - -
145
Table 18. Trend slope values for model 3-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - - - - 0.0944
AYVALIK -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.1208
DİKİLİ -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -1.2501
AKHİSAR -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.9951
KUŞADASI -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -
DİDİM - -0.0002 - - - -
BODRUM - -0.0002 -0.0002 - - -0.3317
DALAMAN -0.0002 -0.0003 -0.0004 -0.0006 -0.0007 -2.5499
ANAMUR -0.0003 -0.0004 -0.0005 -0.0007 -0.0007 -3.2585
SİLİFKE -0.0004 -0.0005 -0.0005 -0.0007 -0.0008 -1.9831
İSKENDERUN -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.6765
FİNİKE -0.0004 -0.0004 -0.0005 -0.0007 -0.0008 -3.4102
KAŞ -0.0003 -0.0004 -0.0005 -0.0007 -0.0008 -2.5599
SALİHLİ -0.0003 -0.0004 -0.0004 -0.0005 -0.0006 -0.8362
SEFERİHİSAR - -0.0003 -0.0003 -0.0004 -0.0005 -0.7297
ÖDEMİŞ -0.0003 -0.0005 -0.0005 -0.0006 -0.0007 -1.3885
NAZİLLİ -0.0003 -0.0004 -0.0005 -0.0007 -0.0008 -1.5202
ELMALI -0.0005 -0.0006 -0.0008 -0.0010 -0.0011 -1.9958
MUT -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -1.3588
KARATAŞ -0.0002 -0.0003 -0.0003 -0.0004 -0.0005 -1.3051
MENEMEN -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.0065
FETHİYE -0.0002 -0.0003 -0.0004 -0.0006 -0.0007 -3.1756
MARMARİS -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -1.4533
BURHANİYE -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.7963
MİLAS -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -1.2424
YATAĞAN -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -1.7317
KOZAN -0.0003 -0.0003 -0.0004 -0.0005 -0.0006 -
DATÇA -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -0.6776
KÖYCEĞİZ -0.0003 -0.0005 -0.0006 -0.0008 -0.0009 -2.7808
KORKUTELİ -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -1.7738
KARAİSALI -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -2.7659
MANAVGAT -0.0003 -0.0003 -0.0004 -0.0005 -0.0006 -2.7792
ERDEMLİ -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -2.0348
146
Table 18. (cont’d) Trend slope values for model 3-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0002 -0.0003 -0.0003 -0.0004 -0.0005 -1.1572
DÖRTYOL -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -2.3914
ISLAHİYE -0.0005 -0.0006 -0.0007 -0.0008 -0.0009 -2.2514
GAZİPAŞA -0.0003 -0.0003 -0.0005 -0.0006 -0.0006 -2.6127
YUMURTALIK -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -1.6012
SAMANDAĞ -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.8287
ACIPAYAM -0.0004 -0.0006 -0.0007 -0.0009 -0.0010 -1.6232
TEFENNİ -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -
GEMLİK - - - - 0.0002 -
KARACABEY - - - - - 0.2343
MUDANYA - - 0.0003 0.0004 0.0004 -
M.KEMALPAŞA - - - - - 0.2164
AYVACIK -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.2506
OSMANIYE -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.9880
ALANYA -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -
MANISA -0.0002 -0.0002 -0.0002 -0.0003 -0.0003 -0.4944
IZMIR -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.2204
AYDIN -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.3892
DENIZLI -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -0.8954
MUGLA -0.0004 -0.0005 -0.0007 -0.0008 -0.0009 -3.1253
ANTALYA -0.0004 -0.0004 -0.0005 -0.0007 -0.0008 -6.8051
MERSIN -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -2.0581
ADANA -0.0002 -0.0004 -0.0004 -0.0005 -0.0006 -1.5713
ANTAKYA -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -
BALIKESİR -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -0.6198
CANAKKALE -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -
BURSA -0.0001 - - - 0.0001 -
147
Table 19. Trend slope values for model 3-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - 0.0002 0.0003 0.0003 0.0004 0.9017
AYVALIK -0.0001 - - - - -
DİKİLİ -0.0001 - - - -0.0002 -
AKHİSAR -0.0002 - - - -0.0002 -
KUŞADASI -0.0002 -0.0002 -0.0002 -0.0003 - -
DİDİM -0.0002 -0.0002 - - - -
BODRUM -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -
DALAMAN -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.9095
ANAMUR - -0.0002 -0.0003 -0.0004 -0.0005 -1.2869
SİLİFKE -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -1.4583
İSKENDERUN -0.0001 - - - - -
FİNİKE -0.0002 -0.0004 -0.0006 -0.0008 -0.0009 -4.1823
KAŞ -0.0003 -0.0004 -0.0006 -0.0008 -0.0009 -2.6461
SALİHLİ -0.0002 -0.0002 - -0.0002 -0.0002 -
SEFERİHİSAR - - - - - -
ÖDEMİŞ -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.1531
NAZİLLİ -0.0001 - - - - -
ELMALI -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.4453
MUT -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -
KARATAŞ -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -1.9938
MENEMEN -0.0002 - - - -0.0002 -
FETHİYE -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -1.6547
MARMARİS -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -2.1082
BURHANİYE -0.0001 - - - -0.0002 -
MİLAS -0.0002 -0.0003 -0.0003 -0.0004 -0.0005 -1.2091
YATAĞAN -0.0002 -0.0002 -0.0003 -0.0003 -0.0004 -0.8074
KOZAN -0.0002 - -0.0002 - -0.0002 -
DATÇA -0.0002 -0.0003 -0.0004 -0.0004 -0.0005 -0.9445
KÖYCEĞİZ -0.0002 -0.0003 -0.0004 -0.0005 -0.0006 -2.4524
KORKUTELİ -0.0003 -0.0005 -0.0007 -0.0008 -0.0010 -2.6903
KARAİSALI -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.4494
MANAVGAT -0.0001 -0.0002 -0.0003 -0.0004 -0.0005 -1.9299
ERDEMLİ - -0.0001 -0.0002 -0.0002 -0.0003 -0.6527
148
Table 19. (cont’d) Trend slope values for model 3-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.2249
DÖRTYOL - - - - - -
ISLAHİYE -0.0003 -0.0003 -0.0003 -0.0003 -0.0004 -1.2682
GAZİPAŞA - -0.0001 -0.0002 -0.0002 -0.0003 -
YUMURTALIK -0.0002 -0.0002 -0.0002 -0.0002 -0.0003 -
SAMANDAĞ -0.0003 -0.0003 -0.0004 -0.0004 -0.0005 -1.8372
ACIPAYAM -0.0002 -0.0002 -0.0002 -0.0003 -0.0003 -
TEFENNİ -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -0.4529
GEMLİK - 0.0002 0.0003 0.0004 0.0005 0.9707
KARACABEY - 0.0002 0.0003 0.0004 0.0005 0.7738
MUDANYA - 0.0002 0.0003 0.0004 0.0005 0.8824
M.KEMALPAŞA - - - - - -
AYVACIK -0.0001 -0.0002 -0.0002 -0.0002 -0.0002 -
OSMANIYE - - - - - -
ALANYA - - -0.0002 -0.0003 -0.0003 -1.1261
MANISA -0.0001 - - - - -
IZMIR -0.0002 -0.0002 -0.0002 -0.0003 -0.0003 -
AYDIN -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -0.9821
DENIZLI -0.0001 - - - - -
MUGLA -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -2.9318
ANTALYA -0.0002 -0.0004 -0.0006 -0.0007 -0.0008 -4.6493
MERSIN -0.0001 -0.0003 -0.0003 -0.0004 -0.0005 -1.3385
ADANA -0.0002 -0.0003 -0.0004 -0.0005 -0.0005 -1.5819
ANTAKYA -0.0003 -0.0003 -0.0004 -0.0005 -0.0006 -1.4510
BALIKESİR - - 0.0001 0.0001 0.0002 -
CANAKKALE - - - - - -
BURSA - - - - 0.0001 -
149
Table 20. Trend slope values for model 3-3
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA - - - - - -
AYVALIK - -0.0002 - - - -
DİKİLİ - - - - - -
AKHİSAR - - - - - -
KUŞADASI -0.0002 -0.0003 -0.0004 -0.0004 -0.0004 -0.9115
DİDİM - -0.0003 -0.0003 - - -
BODRUM - -0.0003 -0.0003 -0.0004 -0.0004 -
DALAMAN -0.0002 -0.0004 -0.0005 -0.0006 -0.0006 -2.6239
ANAMUR -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.5644
SİLİFKE -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.3257
İSKENDERUN -0.0003 -0.0003 -0.0003 -0.0004 -0.0005 -1.1992
FİNİKE -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -3.0494
KAŞ -0.0003 -0.0004 -0.0006 -0.0007 -0.0008 -2.0672
SALİHLİ - -0.0003 -0.0003 -0.0004 -0.0004 -0.5154
SEFERİHİSAR - - - - - -
ÖDEMİŞ - -0.0002 -0.0002 -0.0002 -0.0002 -
NAZİLLİ - - - - - -
ELMALI - -0.0003 -0.0004 -0.0004 -0.0005 -0.3509
MUT -0.0001 -0.0002 -0.0003 -0.0003 -0.0004 -0.2685
KARATAŞ -0.0003 -0.0004 -0.0004 -0.0005 -0.0006 -1.9121
MENEMEN - -0.0003 -0.0004 -0.0004 -0.0004 -
FETHİYE -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.9081
MARMARİS -0.0002 -0.0004 -0.0005 -0.0005 -0.0006 -1.7822
BURHANİYE - -0.0002 -0.0002 -0.0002 -0.0003 -
MİLAS - -0.0002 -0.0002 -0.0002 -0.0002 -0.4515
YATAĞAN - -0.0003 -0.0004 -0.0005 -0.0006 -0.7760
KOZAN -0.0003 -0.0005 -0.0006 -0.0006 -0.0007 -2.1659
DATÇA -0.0003 -0.0004 -0.0006 -0.0006 -0.0007 -2.6884
KÖYCEĞİZ - -0.0004 -0.0004 -0.0005 -0.0006 -1.6422
KORKUTELİ -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -2.0579
KARAİSALI -0.0004 -0.0006 -0.0007 -0.0008 -0.0008 -2.1444
MANAVGAT -0.0002 -0.0004 -0.0004 -0.0005 -0.0006 -2.2814
ERDEMLİ -0.0002 -0.0004 -0.0005 -0.0006 -0.0007 -1.1042
150
Table 20. (cont’d) Trend slope values for model 3-3
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -1.4530
DÖRTYOL -0.0003 -0.0003 -0.0003 -0.0003 -0.0003 -
ISLAHİYE -0.0004 -0.0005 -0.0006 -0.0006 -0.0007 -2.3811
GAZİPAŞA -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -1.4562
YUMURTALIK -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -1.6826
SAMANDAĞ -0.0004 -0.0005 -0.0005 -0.0006 -0.0007 -1.7906
ACIPAYAM - - -0.0002 -0.0002 -0.0002 -
TEFENNİ -0.0002 -0.0003 -0.0003 -0.0004 -0.0004 -0.4668
GEMLİK -0.0001 - - - - -
KARACABEY - - - 0.0003 0.0003 -
MUDANYA - - 0.0001 - - -
M.KEMALPAŞA -0.0001 - - - - -
AYVACIK -0.0003 -0.0004 -0.0005 -0.0006 -0.0006 -1.7674
OSMANIYE -0.0003 -0.0003 -0.0002 - - -
ALANYA -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -2.1112
MANISA - -0.0002 -0.0002 -0.0003 -0.0003 -
IZMIR -0.0002 -0.0003 -0.0003 -0.0003 -0.0004 -0.6595
AYDIN - - - - - -
DENIZLI - -0.0003 -0.0003 -0.0003 -0.0003 -0.2515
MUGLA -0.0003 -0.0004 -0.0006 -0.0006 -0.0007 -3.1938
ANTALYA -0.0003 -0.0005 -0.0006 -0.0007 -0.0008 -1.9951
MERSIN -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -1.2421
ADANA -0.0003 -0.0004 -0.0005 -0.0005 -0.0006 -1.4225
ANTAKYA -0.0003 -0.0003 -0.0004 -0.0005 -0.0005 -0.4881
BALIKESİR -0.0002 - - - - -
CANAKKALE - - - - - -
BURSA -0.0001 -0.0001 - - - -
151
Table 21. Trend slope values for model 4-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -1.2155
AYVALIK -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -1.4128
DİKİLİ -0.0004 -0.0006 -0.0007 -0.0007 -0.0008 -1.5068
AKHİSAR -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -1.6499
KUŞADASI -0.0005 -0.0007 -0.0008 -0.0009 -0.0010 -1.5502
DİDİM -0.0005 -0.0008 -0.0009 -0.0010 -0.0011 -1.8023
BODRUM -0.0006 -0.0009 -0.0010 -0.0012 -0.0013 -1.8496
DALAMAN -0.0005 -0.0009 -0.0011 -0.0012 -0.0013 -3.9283
ANAMUR -0.0004 -0.0007 -0.0010 -0.0012 -0.0014 -2.0766
SİLİFKE -0.0004 -0.0007 -0.0010 -0.0012 -0.0013 -1.9075
İSKENDERUN -0.0005 -0.0008 -0.0010 -0.0012 -0.0013 -2.2981
FİNİKE -0.0006 -0.0009 -0.0011 -0.0013 -0.0014 -2.8071
KAŞ -0.0005 -0.0008 -0.0011 -0.0012 -0.0013 -2.1842
SALİHLİ -0.0005 -0.0007 -0.0009 -0.0011 -0.0012 -1.6147
SEFERİHİSAR -0.0004 -0.0006 -0.0008 -0.0009 -0.0009 -0.7805
ÖDEMİŞ -0.0005 -0.0007 -0.0009 -0.0011 -0.0013 -2.0717
NAZİLLİ -0.0003 -0.0005 -0.0008 -0.0009 -0.0010 -0.6492
ELMALI -0.0004 -0.0007 -0.0009 -0.0010 -0.0011 -0.5104
MUT -0.0003 -0.0007 -0.0009 -0.0011 -0.0012 -0.6598
KARATAŞ -0.0005 -0.0008 -0.0010 -0.0012 -0.0013 -1.8939
MENEMEN -0.0005 -0.0007 -0.0009 -0.0010 -0.0011 -1.9823
FETHİYE -0.0005 -0.0008 -0.0010 -0.0011 -0.0013 -2.4982
MARMARİS -0.0006 -0.0009 -0.0012 -0.0013 -0.0014 -3.1877
BURHANİYE -0.0004 -0.0005 -0.0006 -0.0007 -0.0007 -0.7858
MİLAS -0.0004 -0.0007 -0.0008 -0.0009 -0.0010 -1.5322
YATAĞAN -0.0005 -0.0007 -0.0010 -0.0011 -0.0013 -1.5941
KOZAN -0.0006 -0.0008 -0.0011 -0.0012 -0.0013 -2.9038
DATÇA -0.0006 -0.0010 -0.0012 -0.0013 -0.0014 -3.5946
KÖYCEĞİZ -0.0005 -0.0007 -0.0010 -0.0011 -0.0012 -3.0215
KORKUTELİ -0.0005 -0.0007 -0.0009 -0.0011 -0.0011 -2.3294
KARAİSALI -0.0005 -0.0009 -0.0011 -0.0012 -0.0013 -2.0062
MANAVGAT -0.0004 -0.0007 -0.0010 -0.0012 -0.0013 -3.4744
ERDEMLİ -0.0003 -0.0005 -0.0009 -0.0011 -0.0013 -1.1609
152
Table 21. (cont’d) Trend slope values for model 4-1
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0006 -0.0009 -0.0010 -0.0012 -0.0013 -1.8455
DÖRTYOL -0.0004 -0.0006 -0.0008 -0.0010 -0.0011 -2.2443
ISLAHİYE -0.0006 -0.0010 -0.0012 -0.0014 -0.0016 -3.7407
GAZİPAŞA -0.0004 -0.0007 -0.0010 -0.0012 -0.0013 -3.0907
YUMURTALIK -0.0006 -0.0009 -0.0011 -0.0012 -0.0013 -2.2480
SAMANDAĞ -0.0006 -0.0009 -0.0011 -0.0013 -0.0014 -3.0354
ACIPAYAM -0.0004 -0.0007 -0.0008 -0.0010 -0.0011 -0.8360
TEFENNİ -0.0005 -0.0007 -0.0010 -0.0011 -0.0013 -1.2053
GEMLİK -0.0005 -0.0007 -0.0009 -0.0010 -0.0012 -2.8118
KARACABEY -0.0003 -0.0004 -0.0005 -0.0006 -0.0007 -0.6614
MUDANYA -0.0004 -0.0005 -0.0006 -0.0007 -0.0008 -1.4393
M.KEMALPAŞA -0.0004 -0.0006 -0.0007 -0.0008 -0.0009 -1.2135
AYVACIK -0.0005 -0.0008 -0.0010 -0.0011 -0.0012 -2.7502
OSMANIYE -0.0003 -0.0005 -0.0007 -0.0009 -0.0010 -1.3446
ALANYA -0.0004 -0.0007 -0.0010 -0.0011 -0.0012 -3.5498
MANISA -0.0004 -0.0007 -0.0009 -0.0010 -0.0011 -1.1182
IZMIR -0.0004 -0.0007 -0.0008 -0.0009 -0.0010 -1.7293
AYDIN -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -1.2404
DENIZLI -0.0004 -0.0007 -0.0009 -0.0011 -0.0012 -0.8129
MUGLA -0.0007 -0.0010 -0.0012 -0.0013 -0.0015 -5.6805
ANTALYA -0.0005 -0.0008 -0.0010 -0.0012 -0.0013 -1.8437
MERSIN -0.0003 -0.0006 -0.0009 -0.0011 -0.0012 -1.1522
ADANA -0.0006 -0.0009 -0.0011 -0.0012 -0.0014 -2.0974
ANTAKYA -0.0005 -0.0008 -0.0010 -0.0012 -0.0013 -0.8290
BALIKESİR -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -1.0592
CANAKKALE -0.0002 -0.0003 -0.0004 -0.0004 -0.0004 -
BURSA -0.0005 -0.0008 -0.0010 -0.0012 -0.0013 -4.2393
153
Table 22. Trend slope values for model 4-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
BANDIRMA 0.0003 0.0004 0.0006 0.0009 0.0010 2.1309
AYVALIK 0.0003 0.0006 0.0008 0.0011 0.0012 4.0884
DİKİLİ 0.0005 0.0008 0.0012 0.0015 0.0016 11.1233
AKHİSAR - - 0.0003 0.0004 0.0004 -
KUŞADASI 0.0003 0.0004 0.0007 0.0010 0.0012 4.3631
DİDİM 0.0001 0.0002 0.0004 0.0006 0.0006 2.5433
BODRUM - - - - - -
DALAMAN 0.0001 0.0002 0.0004 0.0006 0.0008 3.3405
ANAMUR -0.0002 -0.0003 -0.0005 -0.0007 -0.0008 -1.8209
SİLİFKE -0.0003 -0.0005 -0.0006 -0.0008 -0.0009 -1.1679
İSKENDERUN -0.0003 -0.0004 -0.0006 -0.0007 -0.0008 -1.2993
FİNİKE -0.0003 -0.0004 -0.0006 -0.0008 -0.0010 -2.7210
KAŞ -0.0002 -0.0002 -0.0004 -0.0005 -0.0007 -1.9564
SALİHLİ -0.0004 -0.0006 -0.0008 -0.0009 -0.0010 -2.2055
SEFERİHİSAR 0.0001 0.0002 0.0004 0.0005 0.0006 1.2161
ÖDEMİŞ - - - - - -
NAZİLLİ -0.0001 - -0.0003 -0.0003 -0.0004 -
ELMALI -0.0006 -0.0008 -0.0010 -0.0012 -0.0014 -2.7304
MUT -0.0004 -0.0006 -0.0008 -0.0010 -0.0011 -1.0511
KARATAŞ - - - - - -0.9660
MENEMEN 0.0003 0.0005 0.0008 0.0010 0.0012 5.6682
FETHİYE 0.0000 - 0.0002 0.0003 0.0004 1.5669
MARMARİS - - - - - -
BURHANİYE 0.0003 0.0006 0.0008 0.0011 0.0012 3.7722
MİLAS - 0.0002 0.0004 0.0006 0.0007 3.4625
YATAĞAN -0.0005 -0.0007 -0.0010 -0.0012 -0.0013 -2.8793
KOZAN -0.0001 - - - - -
DATÇA - - - - - -
KÖYCEĞİZ - - 0.0002 0.0003 0.0004 2.5084
KORKUTELİ -0.0006 -0.0008 -0.0010 -0.0012 -0.0014 -3.5397
KARAİSALI -0.0002 - -0.0003 -0.0004 -0.0004 -1.0600
MANAVGAT 0.0001 0.0002 0.0005 0.0007 0.0009 4.2760
ERDEMLİ -0.0003 -0.0004 -0.0005 -0.0007 -0.0009 -1.0033
154
Table 22. (cont’d) Trend slope values for model 4-2
Station SPI 1 SPI 3 SPI 6 SPI 9 SPI 12 Annual Pr.
CEYHAN -0.0002 - - - - -
DÖRTYOL 0.0002 0.0003 0.0004 0.0006 0.0007 3.3084
ISLAHİYE -0.0006 -0.0009 -0.0012 -0.0014 -0.0015 -5.0346
GAZİPAŞA - 0.0002 0.0003 0.0005 0.0006 1.8991
YUMURTALIK -0.0001 - - - - -
SAMANDAĞ -0.0002 -0.0004 -0.0005 -0.0007 -0.0008 -4.5645
ACIPAYAM -0.0006 -0.0008 -0.0010 -0.0012 -0.0013 -2.1494
TEFENNİ -0.0005 -0.0008 -0.0010 -0.0011 -0.0012 -1.9704
GEMLİK 0.0003 0.0005 0.0006 0.0008 0.0009 4.1890
KARACABEY 0.0001 0.0003 0.0004 0.0005 0.0005 1.0010
MUDANYA 0.0002 0.0004 0.0006 0.0007 0.0008 1.8873
M.KEMALPAŞA - - - - - -
AYVACIK 0.0003 0.0006 0.0009 0.0012 0.0014 6.0496
OSMANIYE - - - - - -
ALANYA 0.0001 0.0002 0.0003 0.0005 0.0006 2.0866
MANISA -0.0002 -0.0003 -0.0004 -0.0006 -0.0007 -0.9838
IZMIR 0.0002 0.0004 0.0006 0.0009 0.0010 5.2708
AYDIN - - - - - -
DENIZLI -0.0006 -0.0008 -0.0011 -0.0013 -0.0014 -2.6969
MUGLA - - - - - -
ANTALYA -0.0002 -0.0002 -0.0003 -0.0004 -0.0005 -1.3877
MERSIN -0.0002 -0.0003 -0.0004 -0.0005 -0.0007 -0.8997
ADANA -0.0001 - - - - -
ANTAKYA -0.0004 -0.0007 -0.0010 -0.0012 -0.0014 -2.3972
BALIKESİR - - - - - -
CANAKKALE 0.0004 0.0007 0.0010 0.0013 0.0014 4.1352
BURSA - - - - - -